I don't think it's the idea of 2H not to counterattack, it's more that a perfect guard is meant for a counterattack. However, a perfect guard on a Rabby does
jack shit. Most enemies it stuns for a bit longer, allowing you to get a few more hits off or a stunlock in, but with these guys you knock them back a bit and they keep on coming. But even then, this is basically the only enemy in the game that does this.
2H play against Rabbys generally doesn't involve guarding. If you're playing the balanced way, then one should do a couple hits them reposition, of if you're playing the unbalanced way, a couple shield cancel hits will kill them. For these reasons (and the fact that they're so weak in the first place) means I think that guarding of any sort isn't intended to be used on Rabbys.
Basically, if you're guarding at all, make it a perfect guard. Otherwise running away is a much better solution