Agree that it's best to make a lot of mistakes in smaller boats and then move up. Though I had crewed on a neighbor's 24' boat as a kid, my best experiences then were alone in a sailing dinghy.
Years later, my then lady friend (now wife) and I did sailing lessons on the Chesapeake. It all came back quickly.
Ten years later, we did ASA classes and bought our 34' boat the next year. We fumbled about for the first month but eventually got it together, enough to cross Lake Michigan (80 mi) overnight in 20 kt winds at the end of our first season.
I recommend a formal class every 5-10 years to clean out the cobwebs and inspire more practicing of skills on one's own boat.
And I'd like to get back on a little boat with a centerboard again, one of thes summers!