I've seen team mates switch together (from the perspective of being part of that dynamic,even). It doesn't take all that much effort or coordination if nobody on the team has recently switched (and, quite frankly, squad-mates don't tend to unless the squad elects to - on squad nights, at least). I've seen large squads partially switch and then fight each other. This isn't a new idea but it is actually a pretty decent one. It places no unreasonable demand on the game designer to make a major change in code, it leaves a switch time limit to mollify the spy paranoiacs, it encourages players to move around and meet their occasional or even regular opponents (giving a bit more perspective).
The best part is the group can indeed re-group (if split) or change to their original side (or even yet a different side) in another six hours. Granted, few squads stay on a straight six hours now like some did in the 'grand old days' (squads have shrunk, many of us have gotten older, meaning players who started the game as kids probably now have jobs and/or their own kids - players who started out older .... are even older and stamina/endurance may not be what it used to be). That still means when everyone logs back on together they can reassess and react accordingly.
It comes down to priorities. If a player (or group) refuses to be flexible enough and just MUST have access to all rides no matter how much their side has a numerical advantage (or they have that peculiar 'chess piece loyalty' fetish) then it isn't really a 'broken design' they are complaining about. Sure, it's a game ... but even games may mimic life and you can't please everyone all of the time.
(P.S. If a player or group just can't stand that option, there's always the AvA. I spent years promoting that place and would still love to see others fall in love with it. And, of course, there's the best part of AH, IMHO .... events.)