Gave this a try last week- pretty much followed same recipe with couple minor changes. Grain bill is same, but I used amarillo hops to get to 22-25 ibu's. I was going for a riff on goose island's Sofie (I didn't say clone!) which is a twist on Orval from what I've read. I mashed slightly higher too (150-152). Pitched a healthy stepped up Brett L starter. Lag time was 24-30 hours, then she took off. Started off low-65*- but after a day ramped it up to 72-75*. The Krausen looked weird-not like some pellicles I've seen. I will try to get a pic.
I plan on letting it go 6-8 weeks, racking to clear, and hitting it with a touch of orange peel (a la Sofie). I hope I can hold out several months. I get the feeling this is going to be a nice summer brew.
Alcohol may be man's worst enemy, but the bible says love your enemy.