Yeah, I was wondering where you'd read a followup that said more than that, but this "success" doesn't negate the general point that it's not something you can count on.
It's certainly *possible* that if you threaded a Mac Plus analog board's yoke onto a randomly chosen 12" CRT it would produce a usable picture. But it has to be noted that the compact Mac analog board is also fairly notorious for being sort of marginally spec'ed for the job it does with the *stock* CRT so even if nothing else goes wrong the additional load from driving a bigger CRT might badly shorten its lifespan. Said analog board is also lacking in pots to adjust items like linearity, so if there's any distortion on the larger monitor (which is a distinct likelyhood unless you use a tube with exactly the same deflection angle and screen curvature of the smaller CRT) they'll be no way to fix it without component swaps. Even in the text for the PMGSP he admits that he never quite got the geometry right because he "used up" all the available range, IE: "The display is sharp and clear, but fails to use the full width of the screen...", in the adjustment available on the mono monitor's board, and the pictures do seem to back up that it's a little vertically stretched.
Having an "imperfect" screen certainly might be acceptable for someone building a "hackmac" for shock value; heck, it might even be cyberpunk-ish desirable if you call the thing an art project, but... still, at the very least someone embarking on this should at least *attempt* to know what they're doing beyond "The sockets match and I heard about some guy who did the opposite and it worked!". At least look up the datasheets for the CRT tubes and verify they're at least mostly matching in their electrical requirements? And don't kill yourself.
(And... although, yes, it's your own business what you do with your own stuff, but there are still other sources for monochrome CRTs (mono monitors, 12" B&W TVs, etc) that don't involve destroying other antique computers. Sigh. And learn to use a freaking soldering iron before you consider yourself qualified to do this *at all*, okay? Just swap a few capacitors and freshen up some solder joints, it's relatively easy, rewarding, and eventually all this stuff is going to "die" the same way so it's in the best interest of any computer collector to either learn how to do themselves or make friends with people who can and let *them* decide when something is "dead".)