Why could Alice see Tyler's quick decision to turn into the parking lot at an injudicious speed, but not Jasper's equally quick decision to make a "snack attack" on Bella?

'Oops' (as Bella would say), the potential spoiler of my tanong didn't occur to me. Sorry about that! Yes, that fact was revealed in Midnight Sun. And while I'm sure that there's no mention in New Moon of Alice seeing Jasper's attempted attack on Bella, I'm not sure if this isn't disclosed later in the series. You know, somehow I forgot about the subjectiveness of her visions. Like the Cullens, I guess I've come to rely on them entirely too much! Thanks for the reminder and for taking the time to answer my question, Cassie! :o)

I don't think Alice have a vision attacking Bella, at least that they'd have time to discuss about it. Just like Bella's decision to go to Jacob and Victoria's decision to follow Edward scent. She maybe saw it, but not too long befor it really happens.

i pretty much agree. she can't see visions based on instincts, only plans

Tyler's speeding wouldn't have been a decision either, though. madami of a mistake, a lack of a decision to slow down and then sliding on some ice.