system
Given the following post, respond as if you're commenting on Reddit:
human
[Dragonball] In the World's Martial Arts Tournament, Krillin and Roshi have a fight so quick that the naked eye couldn't perceive it. Why weren't other fights in the series this fast?

Bystanders seemed to have no problem watching future fights. And they were between even more powerful individuals.
gpt
The only watchers who can actually tell whats going on, more than mere moments of the fight, are fighters who have trained to perceive the high speed battle that's occurring. Initially Gohan, for instance, was unable to watch the fight between yamcha and the saibamen.

Normal humans are completely incapable of watching the high speed fights going on.