There is also the possibility that the 'conversational sparkling' you noted is noticeable to many people, and can be faked. If you can project a sense of overwhelming competence without actually acquiring that competence, you get people to defer to you, and that sends you up to the high echelons almost as quickly as the impressive competence itself would.

Also, I know from reliable second-hand observations (family) that much of the high-level power jockeying is "cheating", in the sense that situations which are known to be deteriorating, but whose deterioration is not publicly visible, are pawned off on someone unaware of the problem (i.e. the CEO leaves six months before he sees the crash as likely, and lets the former CFO or something take over) who then takes the fall, through no fault of their own. (This comes from someone who is frequently at the level just below these machinations in a good position to observe, and who has specifically avoided accepting promotions to that level to avoid them. I'm reasonably certain this is not sour grapes.)

I have observed all of this myself; now I wonder what we could observe to distinguish between those possible worlds. How would the world work if 'aliveness' was an honest signal, vs. how would it look if it was a runaway hypersignal, vs. how would it look if smart and clueful people who weren't "alive" were less likely to wind up at those sorts of conferences?