Well, we don't know how much of a factor cauli herself is in doing it as "easily".
Perhaps it's 20 seconds for her, but 5 hours for someone not as gifted, it's an unknown factor at this point.
And it's really cauli that makes it look easy, Cabba was even convinced you can't do it without getting angry first, because you'd be unfamiliar with the sensation until after you transform and get used to it.
And then when she does it anyway he keeps gushing about how awesome cauli is. This seems to me that cauli herself is pretty much a huge variable in doing it so easily, just like how goku himself is a huge variable in him learning the kaio-ken.