[X] Showmanship. It's the showman's aspect that makes wrestling more than just fake fighting. Without it you might as well have picked up boxing. (+1 Showmanship Roll)
She asked what's the most important thing a wrestler can learn not what the most practical thing is, sure safety is practical but it wouldn't really matter how safe your match's were if they were all boring as hell. You can spend the whole match doing nothing but punches and head take downs that you have perfected for maximum safety, no one would tune in to watch it because it would be boring as hell.
Even some of the most safe wrestler's out there like Bret Heart or Kurt Angle knew that showmanship came above even that. Look at The Rock, Stone Cold Steve Austin and Hulk Hogan, these are men that were absolute masters of showmanship.