Actually managed to check on this after having forgotten about it due to a busy week.
The upper and lower jaws were indeed stuck together at a few points, but I was able to carefully wedge a fingernail, then a small screwdriver, into the gap near where the halves met, and carefully lever it open. I stress "carefully", because the next thing that happened was one of the hinge parts on the upper jaw cracked, as that was a weaker point than the inseparable jaws. So I guess now there's an excuse to just leave the damn thing stuck shut.
For all that many of the TR designs hold up (ranging from the meh in Chromedome to the solid in Hardhead to the unexpectedly great in the Triggerhappy mold-sharers and the Jumpstarters), these Headmaster beasts feel like a sick prank. Especially since so, SO little of the rubbery plastic even seemed necessary given the apparent needs of the designs and comparable other pieces. I won't say no to de-Headmastered takes for some if and when they revisit this clutch of characters, but if anyone's getting remade, these painfully compromised designs need to get first dibs.
I wonder if it's worth tracking down the upsized Wei Jiang version. I think it avoids the rubbery plastic (hard to find proper text reviews these days), but then their Mindwipe has all the same rubbery plastic problems. And the tradeoff of this lone dude being weirdly out of scale is off-putting enough.
