You and most fans judge Garrett vs Perfection instead of Garrett vs other realistic options at HC for the Cowboys.
Fans forget that even the best coaches are far from perfect. Belichick is so good that despite having an All-Pro QB, he still has to cheat. I don't even know who is the #2 rated HC but they all have warts. Sean Payton has had his share questionable decision over the years and has had personal problems of some sort. Harbaugh was good for awhile in SF but seemed to burn out players and ownership. Pete Carroll has been doing well but was a huge failure in his 1st NFL HC job when he had less talent. He was also on board with signing Matt Flynn to a 10M per contract when they got lucky and found Wilson.
You and most emotional fans probably won't admit it, but Garrett is much better than Wade Phillips as a HC. Wade ruined the team mentality with his complete lack of discipline and overall ineptness as a Head Coach.
In reality Garrett is probably middle of the pack of NFL Head Coaches.
Actually I don't. It's really a simple question. Is Garrett good enough to win a SB? It's not about being perfect or the greatest ever or better than Jimmy Johnson or whatever else you want to come up with.
And no, you'd be wrong. Garrett is likely a better coach than Phillips. But that's like arguing which would you prefer to eat......... a spoonful of cat turds or a heaping plate of dog poop? Both would be awful, just the cat poop might be a bit more tolerable.
Great coaches do make mistakes. But they typically have far more successes than failures, far more good calls than bad calls, far more good games than bad games, far more sound game plans than bad ones. So when a guy like McCarthy or Payton makes a mistake, you temper that with the understanding that these guys have shown time and time again they are great coaches. When Garrett makes a mistake or has a bad game, you don't have the resume or safety net to fall back on. He made that mistake or had that bad game because it's likely he's just not a very good head coach, a middle of the pack coach like you suggest.
And I firmly believe we are on a 0-5 streak because he's just not a very good head coach. That doesn't mean I think it's 100% his fault. But he has a hand in this mess just like the QBs do, the front office does for even having these bad QBs, etc.
I would be very happy to see Garrett fired at season's end and see Jones go out and get a quality coach to give Romo a fighting chance at a SB run these last few years of his career here.