1. "could of" = "could HAVE"
2. "would of" = "would HAVE"
seriously, english is supposed to be your first language.
3. you bring up a good point with the fix, but I really do think that Duffee is just overrated. Compared to Alistair, he has basically zero stand-up skills, and that showed.
See how many cockneys you can find who say Have not Of.
There is having less skills in stand up and been completely stupid, surly even Duffee should of known not to walk into that clinch and to keeps his hands up when that close to the Reem.