One weak group between two
In judging positions with weak groups in them, the weak groups have a similar effect to negative influence, supposing there was such a thing. That is, weak groups bring some sort of disadvantage, because it may be impossible to ignore certain attacking plays against them unless you want to sacrifice them.
One can guess that it is better to have one weak group than two, but that depends a bit on how weak the groups are, and where. One case where it is rather clear is a weak group that separates the opponent into two weak groups. Any running move with the single weak group will have an effect on both sides - even if the single weak group is difficult to defend initially, that is likely to change after a few plays and the player with the two groups will be the one in trouble.