Trait Question

[Calcifer]

So, I was thumbing through @[Salem] 's genetic requesting threads and saw that there was a question about the difference between self-manipulation and shape-shifting, and naturally this sparked my interest so I looked up both (and I when I say that, I mean I found them on the superpower wiki site) and found that there's some details that help to make the two different.

1.) According to this link, self-manipulators can create new appendages, remove them, and if they practice/master their trait they can gain immortality from re-shaping their molecular structure.

2.) Shapeshifting I don't think allows this ... at first. You can re-shape your own body, but only with what you're given. This link has shapeshifters "potentially" being able to change down to the cellular level, with the added benefits of self-manipulation (i.e. regrowing limbs) if they master their trait.

So, I guess I'm asking if this is the difference between the two? One is a bit more in-depth than the other? Idk.
I always thought of shapeshifters on here being able to shift into non-mythical creatures or maybe a rock or something but I've never had a horse that has self-manipulation so I don't want to write a post up one day that goes crazy overboard. So I'm asking your thoughts about this.