When removing a shard, the Remove Shards from Cluster tutorial (http://docs.mongodb.org/manual/tutorial/remove-shards-from-cluster/#ensure-the-balancer-process-is-active) says that the balancer needs to be active before removing a shard. I was told that this is actually an unnecessary step.

Also, in this section and others, the concepts of a balancer being 'active' vs. 'enabled' are being used interchangeably, even though they refer to different things with the balancer. For example, in that paragraph, it says that "the balancer process must be active". However, it then says that you can "Check the balancer state using the sh.getBalancerState() helper in the mongo shell", which actually returns true if the balancer is enabled, not active (http://docs.mongodb.org/manual/reference/method/sh.getBalancerState/#sh.getBalancerState).