ORIGINAL: Grouse45
In my opinion you could have two categories. Controlled fragmentation or Fragmenting. A Barnes would be controlled, a SST would be fragmenting. This probably wont work either.
Everybody finds way's to protect what they use. Let's just call them all fragmenting and go on to the next subject.
A truly fragmenting bullet would be like a varmint bullet, coming apart in the animal. Other than a couple shed jackets, all my SWs have exited. So it's inaccurate to lump them with a varmint bullet.
Unless you've got a purpose-designed varmint bullet, virtually every ML bullet out there is controlled to variable extents in how much it fragments.
I would think it fair that a SST/SW, Barnes, etc may shed some weight but is not DESIGNED to fragment. Any bullet will fragment if you shoot it fast enough. Either by design or consequence of design, a Leigh is designed to shed a portion of its weight (and more or less stop at that) which is fairly unique, a Nosler Partition is the only other bullet I can think of with that degree of designed detention of the bullet base.