Same way you could tell Jarrett was garbage even with Delhomme throwing him the ball last year. Same way teams evaluate prospects from spread and gimmicky college offenses. It makes evaluation harder but not impossible, basically just ignore overall production and stats and look at the skillset.
Right now alot his problems are typical rookie mistakes and they look alot worse being in the terrible system/playcalling/supporting cast that we have. Footwork is bad, needs to sell the play action much better, looking off defenses and not staring down receivers to name a few. These things can probably be developed in a year or two, the main thing that worries me as I mentioned is that low sidearm throwing motion. Seriously doubt he makes any noise in the NFL if he doesn't fix that.
QBs go thru more growing pains than any other position. it's the one position that the team needs to cater to in order for a rookie to be successful.
that didn't happen for clausen.
when/if it does, his throwing motion might not even be an issue. an o-line that doesn't get pushed back 5 yards as soon as the ball is snapped could sure help.
i'm not a clausen fan...i'm not a fan of QBs period.
one thing i am is smart enough to know is that clausen was placed in a situation that isn't beneficial for any rookie QB, regardless of his throwing motion.