How would 16th, 17th, 18th century Italian fencing masters do in modern competition?

I don't know if this question is appropriate for /r/AskHistorians, but as they would tell you in /r/fencing, the modern sport is rather disconnected with the idea of the martial arts and "if it were sharp." You might as well ask how the 16th century fencing masters would do at tennis or pingpong.

Like most top level athletes, modern olympic fencers train specifically and intensely to win at their sport according to its current rules. Even if an old master were a wonderful athlete, he could not compete with people who train to win fencing tournaments (and are also good athletes). I would be surprised if he scored a single touch in a tournament. Would you expect an olympic fencer to come in and win a Kendo tournament?

Obviously, people who trained to fight with sharp swords would in turn be better at that than people who just want to win fencing tournaments. Despite this, it's good to remember that duels and fencing in the 16th century were just as much social constructs as modern fencing tournaments are today. The techniques for a 1 on 1 duel are not necessarily adapted to a 16th century battlefield, and the old masters understood this and in many cases discussed it explicitly in their writings.