Greg Cosell has been publishing some pretty awesome columns over at Yahoo.com, the latest of which takes on Teddy Bridgewater and Blake Bortles, accurately pointing out that they have mechanical problems that limit the velocity on their deeper throws. It's not a critique I've often seen of either quarterback, but it shows up on film for both players, and is one of the concerns when projecting them to the NFL.
Cosell previously pointed out the physical tools of Logan Thomas, and the mysteries of Johnny Manziel. There's a common thread throughout these writings: no quarterback entering the draft is a finished product. Every one of them has some things they need to learn, and we never really know what they can and can't learn. That makes for uncertainty in projecting these players to the NFL, and it's a major reason behind many NFL 'busts'.
None of the quarterback prospects in this draft are perfect. Teddy Bridgewater may be my personal favorite, but I certainly can see why someone would prefer a Derek Carr, or Johnny Manziel, or Blake Bortles or even Logan Thomas or Zach Mettenberger. It's a question of style, but also a question of what each team thinks they can teach a quarterback, and what they think each quarterback can learn.
This is different for every prospect, and this is the big unknown. If the Bucs think they can fix Bridgewater's or Bortles' mechanical issues, those prospects will be near (or at) the top of their boards. If they think they can harness Manziel's improvisational ability within their structure, he'll rise to the top. If they love Derek Carr's arm strength and think they can compensate for his lack of pocket presence, he'll be the pick.
To a large extent, this requires a lot of trust in the coaches we as fan's can't really have. If the Bucs pass on or select a quarterback, there are going to be reasons for those decisions that we can't really evaluate. We may love a player, but they may see some crucial flaw they can't fix -- and what we may see as a debilitating problem may be just a minor obstacle for the Bucs.
We do know that the team values mobility and a quick release, but how do they view arm strength? Can their system work with a strong arm but a slow release? Do they think they can teach or compensate for pocket presence? I don't know. And only those who know the answers to those questions can accurately project what the Bucs will do in the draft.