They've all tried it, with varying degrees of success. But some years back, they noticed that I never missed. It was like Babe Ruth calling the homer over the wall - I could pick an amount and nail it, every time.
I never made a big deal about it - I just did it. But it got to be a ritual when traveling that my brother or one of my apprentices would gesture at the pump and whisper knowingly to our traveling companions, "Watch this."
I never elaborate. I never discuss it. I just hit my mark, smile while putting the cap back on, and we drive away.
Of course there's a trick to it - it's basically gas-station magic. An illusion. But it's a cool thing to do, and it's cool that other people think it's cool when I do it. But part of what makes it cool is that I'm not the one saying "watch this". Other people are. That's buzz. Writing posts about it, like I'm doing now, is hype.
In publishing, there are places where both are necessary, but the difference is this: hype is about creating awareness, and can be generated by the author, the publisher, and a network of intimates that varies in size depending on the project. But buzz is what happens after - or in some cases, in spite of - the hype. Buzz is what happens among the booksellers, and librarians, and most importantly, the readers.
Anything can be hyped, but buzz happens on its own. Buzz cannot be manufactured - but the circumstances condusive to it can. Lousy work doesn't get much buzz. Buzz can't make something cool if there's no cool there to begin with - and there's no amount of hype that can change that.