Why Ian Book was a steal.

We probably need to pump the brakes on comparing him to Brees or Wilson. Hopefully, our QB coach and Payton can get him to see his passing lanes better. One of the reasons he abandoned the pocket so much is that he could not see. Brees was very good at getting up on his toes and had a very high release point on his throws. Hopefully, that is something they work on with Book (moreso, the elevation of his view). Also, our blocking schemes have helped Brees, so that may aid Book as well. I am curious to see how he progresses with NFL coaching.
The comparison is not to say he is on par with these VETERANS players but that these type of players have paved the way for these 5'11 - 6'0 QB's
That may be the case, but if that is the case, then we are almost certainly not competing for the playoffs because that means Winston and Hill were both bad enough to be supplanted by a rookie.

Not saying it can't happen - just that I honestly hope it doesn't - at least not next season.

I think Book ends up (if he makes the roster) as the 3 and that Hill possibly has his "joker" role slightly reduced to protect him as the 2.

I think Payton want Harris to fill the "joker" role, more like a Tyreek Hill. So Hill may see his gadget plays reduced anyway.

I believe if Book shows any potential in camp and preseason - and shows that the game isn't too fast for him, then Sean will try to work him into the future plans.

I've watched several of the highlight videos and what I see is a guy with a lot of poise and I'm drawn to his footwork. It looks really good in the pocket - and as Bill Walsh proved with Joe Montana and Steve Young, guys with good footwork can do amazing things in the right system.

If we are competing for a playoff run then it may mean Winston has a good handle of the offense and things are clicking, but my projection is that Ian Book will continue to improve throughout the season and Payton may feel comfortable enough (because he has a vision for the player) to insert him into the lineup much like Wilson when he supplanted Flynn in Seattle.

I don't think Payton will bench Winston in favor of Book if Winston is playing well but if this offense starts to stall and Book is installed and the offense gets some life we've all seen these NFL Stories before, no different than Jimmy V vs Lance in SF or Cam vs M. Jones in NE these guys are the starters but the future is behind them.