Arghh, sorry Krill, I'm not trying to cause a fuss or anything here, but I think there is still a valid point missing. Again, I could still be wrong, but I didn't see anything that really addressed what I was after. So, I'll lay out an example to show what I meant:
Two teams, A and B
1) Sequential turns
1) Team A moves an attack stack up to B's city . . .A---->A
2) B is surprised, reinforcements not there yet . . . . . . . A R'<--R
3) Team A attacks, doesn't take city . . . . . . . . . . . . . A R
4) Team B's units HAVE HEALED! Team B uses the units plus the fresh
reinforcements to overwhelm team A's force . . . . . . . . . B
2) Simultaneous turns
1a) Team A moves an attack stack up to B's city. . .A---->A
1b) B is surprised, reinforcements not there yet. . . . . . . . A R'<--R
2a) Team A attacks, doesn't take city . . . . . . . . . . . . . .A R
2b) Team B's units HAVE NOT HEALED! (Becuase it's still the same,
simultaneous turn!) Team B's reinforcements are not enough to overwhelm
team A's force . . . . . . . . . . . . . . . . . .. . . . . . . . . . A [B+R]
3a) Team A can promote, retreat/do whatever; B was not able to counterattack
I understand this might be a subtle point but I think it's real and something to consider; simultaneous turns do have an effect on combat even without double moves. Also, bringing in a third team could make things even more complicated (for instance, one team could be sandwiched in the middle; enemy 1 attacks, then its their turn, then enemy 2 attacks; it's nearly impossible for this team to do anything meaningful then!)