If you mean at the same time, as in two separate performances simultaneously, no no! It will not be the same as two performances reamped individually. If you want to save time, just move all tracks (that go to one amp) into one long track, and then record that. You can use time markers so you can easily move the reamped tracks back to correct offset.
So, for example a quad tracked project that is, say 3 minutes long, you have four guitars:
GTR1A panned 100 % L
GTR1B panned 75 % L
GTR2A panned 100 % R
GTR2B panned 75 % R
So to reamp them, create a track (say, GTR-Reamp) and place the above four tracks one after each other. Then you will have a track that goes on for 4*3 minutes = 12 minutes. Now, start reamping until all four separate tracks have been recorded (12 minutes).
If you want to use two different amps, instead of one 12 minute track, create two 6-minute tracks (2*3 minutes), and send both to different amps. But also, if you can separate them to different rooms, I don't see why you couldn't reamp two amps at the same time, cutting the reamping time to 6 minutes total. In that way, you send one reamp signal to amp1 in room1, and at the same time another reamp signal to amp2 in room2
I believe this is what you mean?