Shit, I thought Yamcha was going to be the secret weapon.
Well, we've had some hints for Gohan being really strong, maybe even stronger than Goku, ever since they came out of the time room. And of course throughout the series Gohan has always been able to spike up in short bursts.
Goku giving a senzu bean to Cell is pretty stupid and an example of the whole saiyan pride going way overboard. Goku had no problem teaming up against Raditz if it was to save his son, and he used help against both Vegeta and Freezer, but now when it comes to saving everyone on earth, he insists on a fair fight. I don't like this characterization of Goku.