The reason that Travis Bean went so high is that it appears that this is the Travis Bean, the main one that Jerry used for a number of years. The full description of the Bean says that he did have a number of Beans, but this was the only Artist (which has a contoured top). The contoured top is visible in most of the photos of Jerry with a Bean. Just because somebody says he had only one Artist doesn't mean that it's true, but you can presume that auction house would have amended the description prior to the auction if it had been challenged. So, the provenance of this instrument is pretty solid, at least at this point.
The Irwin has an colorful history as well, but isn't a guitar that Jerry played publicly. Since his famous Irwins went for nearly a million, it pulled this one up a lot as well.
It goes without saying that Jerry is famous for having played very few guitars, which greatly increases the value of instruments that he owned and have proof.
In the first of the big guitar hero auctions a number of years ago, it was interesting to read the descriptions of some of Eric Clapton's guitars from the catalogue (this was a fund raiser for his Crossroads rehab center). Many of the guitars had comments like somebody gave me this one and it didn't play very well or this is a backup stage guitar that I never used. Of course, he sold Brownie too then.
David Fung