Derek Carr practiced today.

The more I think about the question, re: if DA could succeed with a better QB, or could Carr be better with better coaching?

I think the answer is no and no again. I don't think Carr is coachable enough to get better, just based on his behavior in the midst of all the offensive struggles. Despite DA's Team over Self mantra, Carr has shown not have the leadership chops or demeanor to be a leader of men. Same goes with DA. DA's continually mishandling the QB room and lack of leadership skills to hold players accountable, both were made for each other--a coach who cannot develop or coach a QB, and a QB who has hit the glass ceiling because he hasn't taken accountability for his erratic play on the field.

A sad reflection of this failure is DA again refusing to sit a struggling, hurt QB. I give Carr all the credit in the world for being tough and his ability to "heal" up enough to start, but this crap reminds me of Winston wanting to play with a bunch of injuries because he didn't want to give up his spot to a QB who might play better.

What was the result? Confusion over whether or how hurt Winston was or whether or not he was benched because he was struggling.

It's frustrating to see almost the exact same scenario play out, only because DA refuses to sit Carr lest one of the other QBs plays better (not likely) to highlight what a colossal failure it was to sign Carr in the first place.
It's clear that DA wants to go down with the ship with Pete and Carr instead of trying to make substantive changes to shake up the team and get the most out of the talent they have.