I got it in the mail today. Will report.
Randy Couture has a lot of good things to say about Melanson and his system. He wrote an intro.
Neil Melanson wrote another intro, and reading the intro, Melanson said that he did nothing but triangle attacks from guard for X-amount of time, at the behest of one of his instructors.
He says he has figured out all sorts of ways/tricks to get the triangle sub, against opponents who knew he was only working for the triangle at all times, so they knew what to watch for, etc. He had to develop ways to catch it depending on how they acted in his guard.
Looking forward to checking this out in detail actually!