This came up on Thursday in my game against David but it also happened in a game I had ages ago against Graham's Eldar. The example I'm going to give is a real world example and it probably doesn't seem that useful but, remember, you only need one guy to control an objective.
The last two Space Marines in a squad get shot at by a Land Speeder Typhoon. They take two wounds from Krak Missiles and two wounds from Heavy Bolter fire.
When this happened to David, he went to pick up both models as the unit had suffered two AP3. However, the rules state that with four wounds to allocate to two models, each model must take two wounds but you get to decide which wounds to allocate. So, the solution is simple, allocate the two AP3 wounds to one guy. Yes, he's now dead twice over but you get to take two saves against the remaining guy.
As it turned out, he failed on of his saves and also died but with a bit more luck he would have survived and he would have been claiming an objective at the bottom of turn 5.
Of course if we look at this from the other side of things, it means that it's entirely possible to cause "too many" wounds to a squad. This is one of the reasons I like MSU, you're putting out less regular shots so there's less chance of your special shots wrapping around. Plus if you're shot back, the wounds wrap around quicker than with a big unit.