It's extremely difficult to get a straight answer out of that guy, and even more difficult now that he's banned. In the past it looks like he aimed for 5.3 in process and 5.4-5.45 room temp.
Edit
www.homebrewtalk.com
I still can't understand his smaller offset, though, since many others have measured a room vs. mash temp offset at an average 0.20-0.25. Might be a decoction thing, maybe that really is the key.
Personally, if mash temperature pH is what really matters, then I'm shooting for 5.3 the same way as he is. At room temp, this measures about 5.5-5.55 for me and my malt and my process. But then who cares, at least the mash temperature pH is correct, according to some.