Nothing good comes out of a body count discussion.
It should be avoided if at all possible.
If impossible to avoid humor is the best approach. “Do I need to pull out my calculus textbook for this discussion?”
Most importantly the guy should never let the woman know he thinks she is lying—and of course keep calm no matter what she says.
The goal is to get her off the topic as soon as possible.
If she has a “body count” more than one is comfortable with, Why bother wasting each other’s time?
I would agree that any such discussion is almost doomed to failure - but at least theoretically, such information would be invaluable to the male.
Between 18-29, women are at the height of their SMV, and enjoy an extremely high level of corresponding social power. Many do not use that power wisely. (Modern society actually encourages them to defer settling down until their fertility is already in decline.)
Men, on the other hand, do not "come into their own" until their late 20s / early 30s. Their SMV does not peak until their late 30s. The playing field is thus not level until much later in life.
Most men gain their first dating experiences in a "scarcity environment." Those experiences imprint them. At the same time, women are dating on "easy mode," and their experiences imprint them.
Bitter 40-year-old single women are bitter because they squandered their peak SMV years and gave too freely of their sexual favors. They are now finally learning what it's like to be a normal man early in life.
Bitter 40-year-old men are invariably embittered by divorce (i.e., being taken to the cleaners, losing their children). They are not bitter because they gave too freely of their sexual favors.
The whole situation is asymmetrical but our society teaches us that this is NOT the case.
Regards,