Allow deploying of more than one vmware compute node

The restriction to only one compute node is bad for HA/scale
out reasons, and it seems to be possible to deploy multiple
computes just fine..
I'm not sure I understand.  Why exactly would it be "worthless"?  For example, is there a big difference between assigning 3 compute nodes and 4?  Why not 2 or 5? etc.  3 seems arbitrary to me but maybe I'm missing something.