Tyson does not just talk this - he went out this year ran 45.5 for 400, trained like his life depended on it and even ran a 100m PR (2nd best ever) slightly hurt.
It's called cohones, and it's why Tyson has my eternal respect, despite those who email me to say 'oh stop being nice to Gay, he ducks BOLT constantly'.
I don't think he can run 9.5 - I felt sure he could run right at 9.69 at Worlds which he pretty much did.