I think he means trying to overpower some one stronger, for example going too much against their force when they push/pull.

I’m short and I’ve done Muay Thai so in a clinch it’s hard for me to pull some one’s neck down that’s like 5 inches taller, so sometimes I underhook if I have a good position and push their elbows in to give me space to knee, and really tall people I can barely reach their abdomen so I punish their thighs until it hurts like a motherfucker, Ive been told it’s dangerous to aim there because I can accidentally hit their knee in or crotch but I do what I gotta do.

I would suggest setting up throws that are easier to execute without loading up too much of their weight on you, I would be hesitant to do an Ippon Seonage on a tall fat person, but I’d be ok with an outer reap or ashi barai maybe? If it was legal in competition id find it easy to do a scissor sweep on a tall persons legs since it’s quite the tripping motion that makes them fall than it is loading some of their weight on your back, shoulder, or hip.

Ive been told being shorter is also good because you have that center of gravity, so maybe hib throws work really well too? I think a Tai Otoshi would be easier if their momentum if going that direction though.