User blog comment:KidVegeta/KidVegeta's reviews/@comment-3097771-20110403224211/@comment-3097771-20110403232229

They are never shown to go SS2 in any of the animes. Therefore, if after all that training, if they couldn't, I don't see how they could after just a random introduction. Therer would need to be a good explanation. -KidVegeta