I think anytime a MMA fighter can compete and beat the best of the best in K-1, like Cro cop did with Bonjavski, then you have the qualifications of an elite striker. Cro cop has unique tools that most fighters don't. A southpaw with a powerful left along with an extremely powerful left kick. Most fighters spend a large portion of their training defending against the right hand/kick, it's natural, with Cro Cop its the exact opposite you have to worry about, then you couple in great speed and reflexes, and you get yourself a very narrow window for mistakes.
His boxing was mediocre at best, he telegraphs that left straight. He rarely throws combinations and he has zero head movement. In MMA his boxing is good enough but in "Boxing" hes below average.
Ok why dont we call GSP's wrestling mediocre since he would get beat in the olympic in real wrestling competition ? We are in the forum of MMA, talking about the boxing of one guy in the sport of MMA. His boxing is good in mma, thanks you, I don't care that his boxing suck from a pure boxing point of view.