I've been doing more double-class nights--a "sick workout" one of the instructors, a 24-year-old, called it.
Monday night, a single grappling class, I did really well. Got that instructor in an arm triangle and he really had to work to get out of it. (Then he quickly tied me up in knots, but it's the first time I ever got anything good on him.) Did well against other classmates, including two who weigh 30-50 pounds more than me. One I got into a kimura. One I just got out of a bad position and survived.
Tonight: Double class, standup (kickboxing) then grappling. Two hours. Kickboxing, I did well. Grappling, I did terrible. And I was up against some of the same people.
Amazing the variation.