Crassula umbella therophyte ?

[Jangaudi]

Hi all,
I was wondering to what extend Crassula Umbella (umbellata) is indeed a therophyte, "a plant that survives unfavourable seasons in the form of seeds only", as is described in the llifle entry. I couldn't really find any other information about this. Usually it is described that one can take cuttings from it, and that the leaves will die down during summer rest, and regrow in the fall.
So am I right to assume that in their natural habitat plants might survive several seasons if conditions are right, and only die back and regrow from seeds in unfavourable years, and thus in cultivation they would cease being annuals, taken they get the right care ?
Anyone here growing them ?