Originally Posted by Mendoza
The key word is today. Not very is your answer. Here’s a good rule of thumb. Skilled super heavies with power almost always beat smaller opponents who are not power punchers. Exceptions to the rule would be an injury, or bad judging.
On a fair score card Holyfield is 1-4 vs. Lewis and Bowe.
If you want to use modern examples Adamek was completely outclassed by an olderVitali Klitschko. Byrd was badly beaten twice by Wlad, and was lucky Vitlai was injured. Chambers hardly won a round vs. Wlad. Hide lasted less than 2 rounds vs Vitali. Haye was scared of Wald. Jones would never fight Klitschko, and Toney wisely declined a chance for a title to meet Wlad, and then took a fight for less money and no major belt.
I don’t see how any of the below names, with the possible exception of Dempsey would have a realistic chance of victory. And I say this because Dempsey had great power, good mobility, good speed, and enough reach ( 77” ), and took the fight to his man. Out boxing super heavies with skills since 1990 is very rare. Only Bowe lost one decision and it was a razor thin one at that. Lewis, and Both Klitschkos never lost a decision.
My short answer was: in nearly all cases, not very effective.
Your post was a good, longer answer