splitting 10s bad?

Saw a guy at my table splitting 10s over and over, which is just wild to me. Dealer was showing a 5 or 6 most times, and he’d just split without thinking. I get wanting to pump up the action but from what I know about basic strategy, that's one of the worst moves unless the count is super high and you're playing some weird scenario. Most of us just sat there kind of tight-lipped while he got some dirty looks from others when his move led to dealer pulling a 21.

Anyone actually believe there’s a legit time to do that or is it just asking for trouble? I’m trying to keep my approach structured and stick to math, but maybe I’m missing some angle. Anyone split 10s themselves or have a story where it worked out?