No, it really ticks me off when games decide to auto balance, for instance in left 4 dead I'm playing with friends, then the next match me or a teammate has switched unexpectedly, then one of them either has to leave to switch back or one of them gets kicked, then they cant rejoin.. It's annoying as hell. When I say friends, it doesn't mean we've played together and are a hardcoe team, just means we know each other so it's not pub stomping.
I'd rather have a mild annoyance than keep playing shutouts against a superior team. It's not fun for anyone if the game is ridiculously stacked. Also if 2 people leave on the other team you now have 2 more people. With no auto balance no one will join the other team, and even more people will leave. Games without auto balance and shuffling are terrible.
You're not supposed to leave and switch back, you're supposed to svck it up and play on the other team. I have no sympathy for someone who tries to circumvent a system that was put in place for a reason.