I don't know about the 'Howitzer Method' but Jeff Johnson has discussed the idea of promoting forums on one of his coaching club videos he placed on You tube. The idea is that you talk about the great information you found on the forum and some specific detail that helped you. (Either the products sold or the info on the forum).

As long as you have trackbacks and pingbacks on, you'll get noticed. This works especially on sites where posts are confirmed by the webmaster - After all, they have to read the post before they approve it.

It's just another way of getting known.

Paul McPherson