Louis Blair wrote:
If someone has a copy of No Regrets handy perhaps
they can find something on the Bxh2 move. If I
remember correctly, there was a question about
it in one of the interviews.

I can find only a very brief mention, on page 15. The first press
conference of the 1992 match, on 1 September, had this exchange between
Ivan Solotaroff of Equire magazine and Fischer:

Q: Why did you take on h2 in the game against Spassky in 1972? Were
you trying to create winning chances by complicating a drawn position?
A: Basically, that's right, yes.