It’s been mentioned occasionally in stories about The Monkees for over 50 years now. You must have heard or read about it somewhere along the line.
I read that Mike Nesmith was the only Monkee who was an actual musician when the show started. The others were hired for their looks and offbeat personalities, and only had limited experience. When the show became a hit, the others had to take crash courses in guitar, etc. to sound competent in live performances.