People use the expression "career is taking off like a rocket" for someone who is has attained success quickly, and the author is playing on that expression by saying that although Major has attained success quickly, his path to success was not a normal straight line, like a rocket, but more resembling a balloon with the air being let out, quickly moving, but constantly changing directions, going from one school to the next.

Better question though is why would Applewhite want to steal Ricky's girl?

That's sort of like me dating Heather Grahm after she went "roller skating" with Dirk Diggler.

Tossing a hotdog down a hallway just doesn't seem like much fun...especially given Applewhite's "lack of arm strength and poor accuracy."

By the way, Miss Rhode Island says that guys like her small hands because they think it makes their dicks look bigger.  That'll probably get her a few more votes. Afterall, we can't have her votes garnisheed now can we?