Failover warns about dataloss when it shouldn't

I have a 4 node cluster, fully rebalanced, 1 bucket, 1 replica 1M items,

Checking stats, the cluster is fully balanced and replicated:
========curr itmes :===========
MACHINE: 10.2.1.50
 curr_items: 249990
 curr_items_tot: 499999

MACHINE: 10.2.1.12
 curr_items: 249984
 curr_items_tot: 500005

MACHINE: 10.2.1.13
 curr_items: 250011
 curr_items_tot: 499988

MACHINE: 10.2.1.14
 curr_items: 250015
 curr_items_tot: 500008

and aggregate moxi stats:
root@localhost ~]# /opt/membase/bin/mbstats 127.0.0.1:11211 all | grep curr
 curr_items: 1000000
 curr_items_tot: 2000000

but stats on http://10.2.1.12:8091/pools/default/buckets
shows: "replication":0.5 on two out for the four nodes, hence the warning that you might lose data if you failover.

here are the stats all from these two machines (10.2.1.12, 10.2.1.14)
Sharon-Barrs-MacBook-Pro:scripts sharonbarr$ ./stats 10.2.1.12:11210 all
 accepting_conns: 1
 auth_cmds: 1704
 auth_errors: 0
 bucket_active_conns: 1
 bucket_conns: 53
 bytes_read: 1816953547
 bytes_written: 239436660
 cas_badval: 0
 cas_hits: 0
 cas_misses: 0
 cmd_flush: 0
 cmd_get: 0
 cmd_set: 0
 conn_yields: 25688
 connection_structures: 41
 curr_connections: 20
 curr_items: 249984
 curr_items_tot: 500005
 daemon_connections: 10
 decr_hits: 0
 decr_misses: 0
 delete_hits: 0
 delete_misses: 0
 ep_bg_fetched: 0
 ep_commit_num: 851
 ep_commit_time: 0
 ep_commit_time_total: 52
 ep_data_age: 4
 ep_data_age_highwat: 24
 ep_db_cleaner_status: complete
 ep_db_strategy: multiMTVBDB
 ep_dbinit: 1
 ep_dbname: /opt/membase/var/lib/membase/default-data/default
 ep_dbshards: 4
 ep_diskqueue_drain: 626334
 ep_diskqueue_fill: 585432
 ep_diskqueue_items: 739
 ep_diskqueue_memory: 59120
 ep_diskqueue_pending: 1640908
 ep_expired: 0
 ep_flush_duration: 0
 ep_flush_duration_highwat: 14
 ep_flush_duration_total: 80
 ep_flush_preempts: 0
 ep_flusher_state: running
 ep_flusher_todo: 0
 ep_io_num_read: 0
 ep_io_num_write: 752600
 ep_io_read_bytes: 0
 ep_io_write_bytes: 1526563497
 ep_item_begin_failed: 0
 ep_item_commit_failed: 0
 ep_item_flush_expired: 0
 ep_item_flush_failed: 0
 ep_items_rm_from_checkpoints: 651025
 ep_kv_size: 1064181479
 ep_latency_arith_cmd: 0
 ep_latency_get_cmd: 0
 ep_latency_store_cmd: 0
 ep_max_data_size: 7261388800
 ep_max_txn_size: 1000
 ep_mem_high_wat: 5446041600
 ep_mem_low_wat: 4356833280
 ep_min_data_age: 0
 ep_num_active_non_resident: 0
 ep_num_checkpoint_remover_runs: 450
 ep_num_eject_failures: 0
 ep_num_eject_replicas: 0
 ep_num_expiry_pager_runs: 0
 ep_num_non_resident: 0
 ep_num_not_my_vbuckets: 0
 ep_num_pager_runs: 0
 ep_num_value_ejects: 0
 ep_onlineupdate: false
 ep_onlineupdate_revert_add: 0
 ep_onlineupdate_revert_delete: 0
 ep_onlineupdate_revert_update: 0
 ep_oom_errors: 0
 ep_overhead: 13296296
 ep_pending_ops: 0
 ep_pending_ops_max: 0
 ep_pending_ops_max_duration: 0
 ep_pending_ops_total: 0
 ep_queue_age_cap: 900
 ep_queue_size: 0
 ep_storage_age: 0
 ep_storage_age_highwat: 24
 ep_storage_type: featured
 ep_store_max_concurrency: 10
 ep_store_max_readers: 9
 ep_store_max_readwrite: 1
 ep_tap_bg_fetch_requeued: 0
 ep_tap_bg_fetched: 0
 ep_tap_keepalive: 300
 ep_tmp_oom_errors: 0
 ep_too_old: 0
 ep_too_young: 0
 ep_total_cache_size: 1063466723
 ep_total_del_items: 0
 ep_total_enqueued: 753380
 ep_total_new_items: 667953
 ep_total_persisted: 752600
 ep_vb_total: 512
 ep_vbucket_del: 172
 ep_vbucket_del_avg_walltime: 6755
 ep_vbucket_del_fail: 0
 ep_vbucket_del_max_walltime: 9866
 ep_vbucket_del_total_walltime: 1161932
 ep_version: 1.6.5.3_211_g9531144
 ep_warmed_up: 0
 ep_warmup: true
 ep_warmup_dups: 0
 ep_warmup_oom: 0
 ep_warmup_thread: complete
 ep_warmup_time: 17776
 get_hits: 0
 get_misses: 0
 incr_hits: 0
 incr_misses: 0
 libevent: 2.0.7-rc
 limit_maxbytes: 67108864
 listen_disabled_num: 0
 mem_used: 1077477775
 pid: 27595
 pointer_size: 64
 rejected_conns: 0
 rusage_system: 72.270013
 rusage_user: 125.563911
 tap_checkpoint_end_received: 257
 tap_checkpoint_end_sent: 409
 tap_checkpoint_start_received: 1171
 tap_checkpoint_start_sent: 1420
 tap_connect_received: 646
 tap_mutation_received: 876875
 tap_mutation_sent: 749582
 tap_opaque_received: 2044
 tap_opaque_sent: 1719
 tap_vbucket_set_received: 854
 tap_vbucket_set_sent: 345
 threads: 4
 time: 1303955939
 total_connections: 1720
 uptime: 2258
 vb_active_curr_items: 249984
 vb_active_eject: 0
 vb_active_ht_memory: 6408192
 vb_active_itm_memory: 531693760
 vb_active_num: 256
 vb_active_num_non_resident: 0
 vb_active_ops_create: 249984
 vb_active_ops_delete: 0
 vb_active_ops_reject: 37130
 vb_active_ops_update: 83579
 vb_active_perc_mem_resident: 100
 vb_active_queue_age: 9032000
 vb_active_queue_drain: 370949
 vb_active_queue_fill: 333577
 vb_active_queue_memory: 320
 vb_active_queue_pending: 28694
 vb_active_queue_size: 4
 vb_dead_num: 0
 vb_pending_curr_items: 0
 vb_pending_eject: 0
 vb_pending_ht_memory: 0
 vb_pending_itm_memory: 0
 vb_pending_num: 0
 vb_pending_num_non_resident: 0
 vb_pending_ops_create: 0
 vb_pending_ops_delete: 0
 vb_pending_ops_reject: 0
 vb_pending_ops_update: 0
 vb_pending_perc_mem_resident: 0
 vb_pending_queue_age: 0
 vb_pending_queue_drain: 0
 vb_pending_queue_fill: 0
 vb_pending_queue_memory: 0
 vb_pending_queue_pending: 0
 vb_pending_queue_size: 0
 vb_replica_curr_items: 250021
 vb_replica_eject: 0
 vb_replica_ht_memory: 6408192
 vb_replica_itm_memory: 531772963
 vb_replica_num: 256
 vb_replica_num_non_resident: 0
 vb_replica_ops_create: 250021
 vb_replica_ops_delete: 0
 vb_replica_ops_reject: 4040
 vb_replica_ops_update: 1068
 vb_replica_perc_mem_resident: 100
 vb_replica_queue_age: 1634573000
 vb_replica_queue_drain: 255385
 vb_replica_queue_fill: 251855
 vb_replica_queue_memory: 58800
 vb_replica_queue_pending: 1612214
 vb_replica_queue_size: 735
 version: 1.4.4_451_gfd84269
Sharon-Barrs-MacBook-Pro:scripts sharonbarr$ ./stats 10.2.1.14:11210 all
 accepting_conns: 1
 auth_cmds: 777
 auth_errors: 0
 bucket_active_conns: 1
 bucket_conns: 13
 bytes_read: 2873947322
 bytes_written: 66031192
 cas_badval: 0
 cas_hits: 0
 cas_misses: 0
 cmd_flush: 0
 cmd_get: 0
 cmd_set: 0
 conn_yields: 39047
 connection_structures: 33
 curr_connections: 19
 curr_items: 250015
 curr_items_tot: 500008
 daemon_connections: 10
 decr_hits: 0
 decr_misses: 0
 delete_hits: 0
 delete_misses: 0
 ep_bg_fetched: 0
 ep_commit_num: 1038
 ep_commit_time: 0
 ep_commit_time_total: 70
 ep_data_age: 9
 ep_data_age_highwat: 28
 ep_db_cleaner_status: complete
 ep_db_strategy: multiMTVBDB
 ep_dbinit: 1
 ep_dbname: /opt/membase/var/lib/membase/default-data/default
 ep_dbshards: 4
 ep_diskqueue_drain: 1001941
 ep_diskqueue_fill: 940349
 ep_diskqueue_items: 2648
 ep_diskqueue_memory: 211840
 ep_diskqueue_pending: 5609910
 ep_expired: 0
 ep_flush_duration: 0
 ep_flush_duration_highwat: 17
 ep_flush_duration_total: 109
 ep_flush_preempts: 0
 ep_flusher_state: running
 ep_flusher_todo: 0
 ep_io_num_read: 1024
 ep_io_num_write: 931809
 ep_io_read_bytes: 0
 ep_io_write_bytes: 1890072592
 ep_item_begin_failed: 0
 ep_item_commit_failed: 0
 ep_item_flush_expired: 0
 ep_item_flush_failed: 0
 ep_items_rm_from_checkpoints: 500520
 ep_kv_size: 1063475185
 ep_latency_arith_cmd: 0
 ep_latency_get_cmd: 0
 ep_latency_store_cmd: 0
 ep_max_data_size: 7261388800
 ep_max_txn_size: 1000
 ep_mem_high_wat: 5446041600
 ep_mem_low_wat: 4356833280
 ep_min_data_age: 0
 ep_num_active_non_resident: 0
 ep_num_checkpoint_remover_runs: 360
 ep_num_eject_failures: 0
 ep_num_eject_replicas: 0
 ep_num_expiry_pager_runs: 0
 ep_num_non_resident: 0
 ep_num_not_my_vbuckets: 0
 ep_num_pager_runs: 0
 ep_num_value_ejects: 0
 ep_onlineupdate: false
 ep_onlineupdate_revert_add: 0
 ep_onlineupdate_revert_delete: 0
 ep_onlineupdate_revert_update: 0
 ep_oom_errors: 0
 ep_overhead: 13296216
 ep_pending_ops: 0
 ep_pending_ops_max: 0
 ep_pending_ops_max_duration: 0
 ep_pending_ops_total: 0
 ep_queue_age_cap: 900
 ep_queue_size: 0
 ep_storage_age: 0
 ep_storage_age_highwat: 79
 ep_storage_type: featured
 ep_store_max_concurrency: 10
 ep_store_max_readers: 9
 ep_store_max_readwrite: 1
 ep_tap_bg_fetch_requeued: 0
 ep_tap_bg_fetched: 0
 ep_tap_keepalive: 300
 ep_tmp_oom_errors: 0
 ep_too_old: 0
 ep_too_young: 0
 ep_total_cache_size: 1063474672
 ep_total_del_items: 0
 ep_total_enqueued: 940349
 ep_total_new_items: 500008
 ep_total_persisted: 931809
 ep_vb_total: 512
 ep_vbucket_del: 1024
 ep_vbucket_del_avg_walltime: 1055
 ep_vbucket_del_fail: 0
 ep_vbucket_del_max_walltime: 5499
 ep_vbucket_del_total_walltime: 1081104
 ep_version: 1.6.5.3_211_g9531144
 ep_warmed_up: 0
 ep_warmup: true
 ep_warmup_dups: 0
 ep_warmup_oom: 0
 ep_warmup_thread: complete
 ep_warmup_time: 59422
 get_hits: 0
 get_misses: 0
 incr_hits: 0
 incr_misses: 0
 libevent: 2.0.7-rc
 limit_maxbytes: 67108864
 listen_disabled_num: 0
 mem_used: 1076771401
 pid: 4960
 pointer_size: 64
 rejected_conns: 0
 rusage_system: 56.882352
 rusage_user: 105.676934
 tap_checkpoint_end_received: 104
 tap_checkpoint_end_sent: 86
 tap_checkpoint_start_received: 649
 tap_checkpoint_start_sent: 382
 tap_connect_received: 259
 tap_mutation_received: 1388931
 tap_mutation_sent: 154103
 tap_opaque_received: 1284
 tap_opaque_sent: 774
 tap_vbucket_set_received: 512
 threads: 4
 time: 1303955944
 total_connections: 791
 uptime: 1808
 vb_active_curr_items: 250015
 vb_active_eject: 0
 vb_active_ht_memory: 6408192
 vb_active_itm_memory: 531759625
 vb_active_num: 256
 vb_active_num_non_resident: 0
 vb_active_ops_create: 250015
 vb_active_ops_delete: 0
 vb_active_ops_reject: 24130
 vb_active_ops_update: 770
 vb_active_perc_mem_resident: 100
 vb_active_queue_age: 0
 vb_active_queue_drain: 275339
 vb_active_queue_fill: 250785
 vb_active_queue_memory: 0
 vb_active_queue_pending: 0
 vb_active_queue_size: 0
 vb_dead_num: 0
 vb_pending_curr_items: 0
 vb_pending_eject: 0
 vb_pending_ht_memory: 0
 vb_pending_itm_memory: 0
 vb_pending_num: 0
 vb_pending_num_non_resident: 0
 vb_pending_ops_create: 0
 vb_pending_ops_delete: 0
 vb_pending_ops_reject: 0
 vb_pending_ops_update: 0
 vb_pending_perc_mem_resident: 0
 vb_pending_queue_age: 0
 vb_pending_queue_drain: 0
 vb_pending_queue_fill: 0
 vb_pending_queue_memory: 0
 vb_pending_queue_pending: 0
 vb_pending_queue_size: 0
 vb_replica_curr_items: 249993
 vb_replica_eject: 0
 vb_replica_ht_memory: 6408192
 vb_replica_itm_memory: 531715047
 vb_replica_num: 256
 vb_replica_num_non_resident: 0
 vb_replica_ops_create: 249993
 vb_replica_ops_delete: 0
 vb_replica_ops_reject: 44399
 vb_replica_ops_update: 431031
 vb_replica_perc_mem_resident: 100
 vb_replica_queue_age: 4775846000
 vb_replica_queue_drain: 726602
 vb_replica_queue_fill: 689564
 vb_replica_queue_memory: 211840
 vb_replica_queue_pending: 5609910
 vb_replica_queue_size: 2648
 version: 1.4.4_451_gfd84269
Sharon-Barrs-MacBook-Pro:scripts sharonbarr$