I think a sign of bad coaching is when you give up big leads. It shows that you let your team get complacent and have trouble putting the fire out when the opponent goes on a run. I think McDermott is solid but needs to have more killer instinct with his team.
Another thing I’ve noticed is it looks like he’s putting more air under the ball (ala Russ Wilson) and letting our speedy WRs (Diggs, Brown, Beasley) to run under the ball.