newcomer - that is very interesting.
i first started learning about watches in my early 20s, mostly through advertisements, and then through watch articles and eventually watch magazines at about 25. around that time, i actually had mentally grouped AP/VC/PP together in my head, before i ever heard the term, "the big three." just from the ads i saw, the things i read, and the vibe i got. i just put those 3 at the top of the pile, and i dont think i am from an earlier generation, i mean, im only 30 (even though saying that makes me feel old).
so i find it interesting that though you probably saw much of the same things i did, you processed it differently.
i do think that a lot of people think first of RO/ROO when they hear AP, and that is certainly different than the vibe of VC/PP, but for me, the first image i think of is the equation of time watch, and that is probably because i saw so many ads for it. when i think of AP i think of their very rich history, the fact they are still privately owned and partially by someone of the original family, their many many high complication watches, their constant innovations in haute watchmaking, and their very classy models. the RO/ROO are a nice (the nice ones that is, everyone makes watches that people dont like) afterthought to me. like a tasty dessert after a steak. and for me, that is why i feel they deserve to be planted firmly in "the big three."
sidebar - i also had, and still do have, the impression, that though PP is part of "the big three," i see them as slightly above.