Hahaha! Love those 'you're big and can't possibly climb' stories!
.... About 3 years ago I was doing plenty of climbing while trainig for a 10k climbing century. One guy I worked with was a pretty good mtb'erfrom what I heard. He asked if I wanted to go. Well I'm a roadie not an mtb'er. I had a $200 mtb rigid that I used around town for running errands. He said I hsould go so I did. We tlaked aobut the upcoming ride witha few coworkers tha had ridden with the guy. He's 145 and a good climber they said. ALso has a $2000 mtb. Then the topic of being 145 and me at 220 came up. He said I couldn't possibly carry my weight up a hill like he could.
It was just him and I at the ride. I kept his pace across the campground just trying to keep up. At the start of the climb he said,"you're fast". I had even started yet!
.....We climbed a dried waterfall about a mile long. I rode up then had to wait 10 minutes for him to show up. We ended up cutting the ride short, only 15 miles. I literally rode cirles around him. I had to cause I didn't know the way.
Another coworker wanted to bet me $100 I couldn't keep up with him. He on an mtb and me on my roadie on a flat trail
All bets were off after the mtb ride!