George,
Rapid relative to what? Yes, it can happen quickly, but question is…will it continue, and on a desirable course?
Kundalini is like a freight train: once it gets going, you had better hope the tracks are laid straight, they are clear, clean, and balanced in relation to the speed and weight of that train. All of these are prepared only with a comprehensive hatha program, which does not happen “rapidly.” Without it, you’re in for a rough ride. Pranayama is not anything you should to do separate of Hatha, serious, daily, rigorous pranayama that is. And definitely not from a book or video. It has to be facilitated by an accomplished teacher, IN YOUR PRESENCE.
You have to take a look at what Vivekenanda said also in relative terms: “He who can control prana can control everything,” because at that point there is nothing else. So yes, that would be everything then. In other words, “anything you want” is not what he was saying, but that there will be nothing else you want. That, I believe, is true.
I’ve been practicing 22-plus years, for 16 years daily: 3 rds kapalabhati kumbhaka, 10 rds. anuloma viloma kumbhaka, together with a comprehensive hatha program.
siva