It looks less like “Ta-da! Magic!” and more like “Ta-da! Medallions!” which is basically just being more specific but hey! Medallions!

So if clothing and accessories are physically made for midforms and are changed for a human by the medallion, what if the clothing is removed from the human form, and is out of the range of the medallion? Will it revert back to midform mode?

Sounds like the medallions create a kind of template for the original nonhominid body to shape itself into when taking on a human appearance and a separate one for returning to original/modifying clothing; my brain keeps trying to flowchart the whole thing. I’m assuming that clothes sewn for nonhominid bodies would modify to human-wearables when a medallion gets used as well as vice-versa, right?

It’s the same basic mechanism a normally-operating TARDIS uses to select a form when it lands, automatically blending in with even a complex environment without actually bashing into anything.

It’s possible a sphinx wrote the software.

I assume in full form, nobody needs glasses?