Thinking more about the current model, I'm a little concerned the current abstraction leaks an internal optimization. From the perspective of a command implementor the server combine is just an internal optimization? IOW, from a command perspective, it seems that we should be concerned about tables and shards and let 'server'-related things be plumbing underneath?
We obviously want to well-define how exactly combine will be called (ie. for a given shard result, only ever once). I dunno, it smells a little funny right now, but then again, I know this method-smithing can be exhausting, just trying to get a feel for what others think? Anyone think it's worth going another round on this? Thanks, --tim
