when watching troy talk on tv during the michigan game (the segments were filmed before the game, fresh after his turnover-laden game against purdue), he just seemed so poised and confident. like he was thrilled at the upcoming challenge and was excited to take it on. he spoke clearly, strongly, and with conviction. his eyes are sharp and piercing.
when watching zwick talk on tv, he just doesn't seem comfortable. he makes poor eye contact. you get the sense that he doesn't really believe what he's saying. he seems nervous. he's not exactly mumbling, but his words just don't come across as very strong.
my personal theory about quarterbacking is that you have to have a certain type of personality, an intangible "it" in order to be the best. there are variances to this type of personality, but certain players, for whatever reason, just don't have "it". i feel bad for zwick, because he obviously is a very talented and accomplished player, who wants to win and is very committed. but for whatever reason, maybe because he was so highly recruited, he's just never gotten comfortable. he's too uptight.
the only time i ever saw boeckman on camera, was during the alamo bowl after zwick got injured. he was standing on the sidelines, talking and laughing with somebody, looking totally and completely relaxed. his smile looked so natural and genuine, there was nothing fake about it. even though this is obviously an incredibly small sample size to be making a judgment about a player, i can visualize him having a calm and confident prescence in the huddle, which the team will respond to well. i think a big reason why krenzel was so successful is because of this. the offense would be struggling all game, but because of his demeanor, the team wouldn't get frustrated and start to press, or to question themselves, or to angrily blame others and point fingers. they would just keep going out there with an optimistic mindset, and they would end up delivering the big plays.
that's just my take. personality is more important in a qb than arm strength.