Shuler’s problem in DC was Norv Turner who wanted him to be Troy Aikman, which was not a fit. Plus, Sonny Jurgensen who was on the radio team, made it known he preferred Gus Frerotte during their first training camp. Yes, they drafted Gus in the same draft and created all kinds of problems.
I've had a couple chances to have conversations with Heath (no we're not friends, it's unlikely he'd even remember my name).
He made no bones about it, he stunk it up in Washington and he struggled to do what Turner wanted him to do.
His thing was, he didn't understand why the Skins even wanted him. Turner was adamant he never leave the pocket, never extend a play, everything was timing, etc. He said a couple times in practice his protection broke down, he scrambled a bit and threw a touchdown...and Turner yelled at him and made them run the play over. He'd rather him throw it away than break the pocket and make a play.
People say "he should have come back" and maybe that's true but who knows. The next year Kerry Collins and Steve McNair were high picks. The year Shuler opted to go was a weak year for QBs in the draft.
I think a lot of people discredit Heath because:
He hurt their feelings by not coming back his Sr year (but I contend that if Colquitt stayed heathy we only lose 1 game that year)
He was a bust in the NFL. So was Tebow and countless others. The logic is weird... was Pat Ryan a better college QB than Tebow because he was able to stay on the Jets roster for a decade plus at a low salary?
And lastly...well I won't open that can of worms here.
One thing he did say is that when the Raiders picked him up in 1999, he felt so comfortable in Gruden's system. He said he finally felt "at home" in that type of offense and loved it. No, he wouldn't have beaten out Rich Gannon, but he certainly could have made the roster and extended his career. Who knows what could have happened, but he was tackled in a pre-season game and dislocated/tore tendons on every toe on one foot. I saw him years later (guessing it was 2-3 years) and he still walked with a noticeable limp at that time.