Of course. I've even had football coaches that I hated with a passion, to the point I didn't want to play for them anymore.
However, the NFL is FAR different from high school or anything else, especially bosses at a job. The NFL is a job, first and foremost. You are playing for your job. If you choose to let anything distract you, then you are out on the street stocking shelves at K-Mart. I wasn't playing for a paycheck in high school. I wasn't playing professionally. It was an extracurricular activity where a crowd of 100 parents watched the games, not 100,000+ diehard fans.
My point is that McCargo is playing for his pay, his job, his teammates and his reputation. Play your best, and you get more playing time, which turns into more money or increased value around the league. Don't give an effort or show you care about being there, and that turns into less playing time and less value around the league. I just think there is an overall lackadaisical attitude with McCargo, and I don't see how a d-line coach either makes or breaks it. If he turns this thing around, or continues down the same road, I just don't think the d-line coach is having anything to do with it. JMO.