What's more, Quirrell is a master legilimens; if he's willing to pull off a Groundhog Day attack on her he might as well just read her mind and get it right the first try. There's no point in wasting time, magic, and risk of getting caught when you could just do the job perfectly in 30 seconds.

Having one's mind read for the first time seems to leave some kind of trace; if he's not sure she's ever had her mind read before he shouldn't try it because then Dumbledore or Snape could learn later that someone's been peeking.