system
Given the following post, respond as if you're commenting on Reddit:
human
[Dragon Ball] Why didn't Cell know he was completely outclassed when Gohan transformed into SSJ2?

Freeza couldn't (at least at the time) sense energy so he had no way of knowing exactly how strong Goku was after he went SSJ for the first time. Cell has no excuse. He has an intimate understanding of how ki works, suppressing and raising your powerlevel, and the sensing of energy. 

Shouldn't he have known immediately that Gohan was far beyond his own limit?
gpt
He thought that Gohan was doing the same thing that Trunks did (raising his power, but with an inferior body).

Cell thought that his form, being perfectly designed, would allow him to overpower Gohan anyway.