Evil Ash said:
1) They may have felt they had their QB of the future with McCown
2) Leftwich's leg was broken in 3 places, many scouts were afraid of him becoming like Joe Theisman and never being the same again.
3) When dealing with #2, remember to factor in how much guaranteed money you pay a top 5 player.
4) He had poor workouts, which were most likely related to his injuries
Does that answer your question
Pretty close to what I've read. The big concern about Leftwich's leg is that he had a hairline fracture just above the ankle, he went against doctors advice and continued to play (because he wanted to win games) and it eventually became a fractured left tibia which he played on in the famous teammates carry him down the field game. Had a hairline fracture in the SAME leg the prior year that they inserted a rod into the tibia for, in fact they said that rod actually lessened the severity of the break the next year.
Scouts were very concerned about that leg as a result.
Most of the poor workout stuff was misleading, he needed 6 weeks post college season to rehab, which meant he couldn't run when most teams wanted him to run, so he was not only getting back into game shape, he was being marked down for "ducking" the 40 because he knew he wouldn't run well since he wasn't fully 100% ready to run. Scouts started to say he wasn't "cooperative" as a result.
you can see why he did it, he was rated ahead of Palmer until late in the year, then the leg started him to slide, if he admitted that he couldn't run full speed yet, with all the concern over his leg, it would have made him fall even further. So he simply refused to run for people early on and let them think he was just uncooperative.
HE eventually did run for people, ran a 4.85, and that's what got him back up the board. Everyone agreed he had a better arm than Palmer, and his leadership grades were off the board because of the playing with a broken leg thing.
Great arm, if he stays healthy the sky is the limit.