i feel like i should answer this question. I ate very spicy food the night before the mcat (baad idea), and i was confronted with a variety of fart options during my first section. I ended up holding it in, but strategy should really depends on the type of fart:
Sbd: You gotta let 'er rip, there's really no reason not to. True, though, this is something that requires practice.
Buttbuster: A very loud and powerful fart. Smell is earthy with remnants of egg, beef, and maybe a white zinfandel. Though such a fart will leave your anus smarting, you might as well let this one go if we're just talking about air. In regards to a buttbuster with oily discharge, i'd have to reconsider. It really depends on your level of protection. Is it that old underwear with all the holes in it...then fuhgeddaboudit.
Prairie-doggin: This is a fart that starts out innocently enough, then bam! You start prairie-doggin, and need to pull a penguin walk to get that thing back in place. Obviously, these are to be avoided at all cost. If you feel you fart has significant potential to evolve into praried-dog status, i would hold it in.
Bubble: This is the fart where you feel like you're blowing bubbles; your anus in the magic wand, and yesterday's taco bell value meal is the bubble solution. Again, your level of comfort (in regards to wet stuff in yo' pants) will dictate if you should let this one off.
Choo choo train: This is the fart that feels like it's been trying to escape for the past 5 hours, but just won't come. You need to be very cautious on this one. He's had a lot of time to marinate, and you just don't know what he'll give. It might be a cough an' sputter moment, followed by a quick and unimpressive death. Or bam! You might need a new pair of pants.