Is he a great coach? Yes.
"great coach" is in the eye of the beholder and therefore opinion.
What is fact and not opinion, is that LM has had/is having "great" results of success like no LSU coach who has come before him, national rankings of #5, #3, #1, #17, #8, #2, and currently BCS #7, as well as leading or close to leading the SEC and BCS in wins since 05.
All this done at a time when the SEC rules college football like it never has before.
I'll take my coach having great results and say, "thank you very much, Coach Miles", and others...they can nit-pick this and that all they have a want to.