First, Hopkins didn't lack natural talent, he wasn't lightning fast but he had very good handspeed, he wasn't physically insanely strong but he was a strong middleweight, he wasn't a brutal puncher but he did have good power, and he was quite agile. He just wasn't as naturally gifted as Jones or Mayweather, two of the better pure athletes of the past 20 or 30 years (Jones of course of all-time). His longevity is no excuse, it is prove of his technical mastery. A fighter with flaws technically would not have such success that late into their career unless they had the equilizer, which is power. If you look at all of the great 40-something fighters: Moore, Foreman, Hopkins, and Fitzsimmons who won the lightheavyweight crown when he was 40 (smaller fighters like Duran and Jofre had success in their late 30's which is equivelent to larger fighters in the 40's), there is a common attribute amongst all except Hopkins. Moore is the all-time knockout king, Foreman may have been the hardest hitting heavy of all-time, and Fitz could be argued as the greatest P4P puncher ever. Hopkins had sturdy power, but nothing special. Granted he has fought considerably less than those 3, but Hopkins success this far past his best (where he now lacks most natural talent due to his age) is based entirely on his craft and skill.
But that's not the fight that Roy got knocked out in. He got knocked out in the 2nd Tarver fight, when he wasn't sucking for air at all.
Why would you only use that fight in determining a prime for prime match up? Roy was in better shape/form in the second fight, but was beaten decisively. IMO, two decisive losses (including a KO) should outweigh one close, razor thin win. That's usually the point of a three-fight series.
Yes, if they would have rematched at the time that they were negotiating on HBO, B-Hop would have been the guy to do it...