Thought I'd also throw my hat into this and say this needs a fix badly. I've also gone and gathered an example model if it may help in solving this issue.

Example Image [www.dropbox.com]
.SMD Files [www.dropbox.com]
(I really hope these links work)

Imported with the latest version of Blender Source Tools in Blender 2.83. As you can see the feet and pelvis are completely broken when imported into Blender but are fine when imported into something like Milkshape3D (as an example).

Sometimes it can be minor (as minor as broken bones can be) but other times it can be as bad (or worse) than the above example.

A fix would be greatly appreciated.