RCs should IDEALLY not have breaking changes. You can dice it up any way you want, but it wasn't a final build and there were obviously some rough edges.

Angular 2 is final now and they've committed to no more breaking changes until the next major build (at least 6 months away). If s/he started learning with it today, then ~90% of what s/he was complaining about in this post wouldn't have been a thing. That was my only point.