
Originally Posted by
morteduzionism
If they used full power, which they rarely do. It's even mentioned a couple of times in the show that they[Saiyans] can't use their full power on planets because it was too dangerous.
During the Buu Saga it's even mentioned that the planet Buu/Goku fight on is much denser(or something) and that was the only reason they could fight there.
When Gohan learns to go Super Saiyan, Goku makes him constantly use the form and do things like eat/drink, in order to learn how to control the power.
So no, they shouldn't be destroying planets with every hit.