Why is this even a question? Look at the mans resume: Belfort x2, Rizzo x2, Maurice Smith, Horn, Kohsaka, Randelman, Ortiz, Liddell. 2 time HW Champ, 2 Time LHW Champ First man to win UFC titles in 2 weight classes. And thats all before he retired. Coming out of retirement at age 43 to dominate a much bigger Tim Sylvia to win the HW title for a historic 3rd time cements his legacy as a great if you ask me. Defending the title against Gonzaga who was coming off a devastating upset over Cro Cop only furthers his legacy. If thats not enough then you have recent wins over name opponents like Vera and Coleman.
Ever fight that Couture has and wins is an unbelievable achievement, even if its the likes of Vera and Coleman. Should he beat Evans, Rampage, Machida, Shogun etc then LORD HAVE MERCY ON HIS SOUL.
No of course not, I mean it's completely natural for your head to double in size in your late 30's and early 40's. Just look at Bonds and Clemons....
Do you have trouble reading? Do you know what the phrase "if thats not enough" means? So the fact that Couture is still adding good names to his res in his mid-forties doesn't say anything in terms of his greatness?