Again, it's like Adamant said earlier, Piccolo wasn't thinking logically, Goku actually WAS thinking logically. The only fail Goku made was not realizing Gohan wasn't a Blood Knight like he himself is... which actually makes sense when Goku barely known that Gohan has to take ALOT to get angry to even go into those extreme bouts of fury and fighting people like mad, Goku thought it was a simple switch and boom, Gohan is beating peoples' asses. And yes, Goku really didn't do shit to Cell and Cell would have killed him after that and demoralized fucking everyone, especially Gohan who didn't even believe he was stronger than Goku(which also shows how deluded Gohan was at that point to believe Goku,, his pops, is just that damn strong from sheer respect) and even THEN, it ignores that Gohan ultimately went through with it and was forcefully NOT trying to get angry on purpose, even warning Cell to not make him angry. So yes, there is ALOT of context people miss when it comes to Goku...