There is only one man who has won a Super Bowl coaching the team he once played for.
This kind of thing happens in college all the time; brilliant coach returns to his beloved alma mater and restores the program to glory. Roy Williams at UNC, Jim Harbaugh at Michigan, several others … although I can only think of two at the moment. So maybe not “all the time”, but it does happen.
Not in the NFL. Not until last year. Not until Gary Kubiak. The only NFL player ever to return to his team as head coach and win it all.
Was he a great head coach? No, although he was by consensus considered to be pretty good, and was always well-respected by those around him. Players, press, everyone. But a lifetime record of 82 and 75 is not a great head coach record. Not in the Bill Belichek era.
So no, a good coach but not an all-time great.