OMG lol... Goten nor Trunks never had a tail, it is stated in a Manga. Gohan who is Half saiyan, had a tail and his was even harder to get rid of than Goku's. Some believe Gohan is the most powerful being in the entire universe of DBZ because of this. Yet he was only 1/2 saiyan. Not even Bra, Vegeta and Bulma's second child had a tail and she was 1/2 saiyan. To make things worse, Pan who is only 1 quarter saiyan managed to get an extreme ammount of power by the age of 14 in GT. Yes, some of the timeline in DBZ/GT is a little screwy.
BTW Bulma can get her ass kicked by Chi Chi one on one. Yet Bulma's ammount of IQ could toast ChiChi's.