I'd agree with other beers, but I've noticed as wits sit for awhile, they settle and lose flavor. I wouldn't want to crash it.
But for the person asking about the extra labor - if you have temp control it's not really any extra work, and you're all the quicker to a clearer beer.
Sent from my...
I've made some coffee porters, never used chocolate before though. I use my French press and make it really strong, then add it at kegging time. Last time I made it, it was overpowering for the first couple of weeks, then smoothed out. I might have not mixed it well enough in the keg, though...
This recipe is pretty basic, so nothing special in regards to making it all grain. Have you already purchased the equipment you'll be using? I'd suggest checking out a general all grain tutorial - there's tons of them here, as well as online in general.
I've had a cider batch that I kegged with a strong sulfur smell still present. The odor did not really die down with time in the keg. I've heard people have had good luck with continuously purge the headspace after the beer has been carbed.
You can get flaked wheat at some grocery stores - I had to do that on one occasion, it was in the bulk section (and cheaper than the brew shop, I might add). Does your shop sell wyeast? If so, use their witbier strain.
I don't think 10 mins at 160F is long enough to sterilize the dme addition. I'd be somewhat worried about contamination. I probably would at least have boiled the addition for 10 mins. Not trying to be mr. negative, though. Let us know how it turns out.
The overstated (but good) advice - don't dump your beer! Especially early on. Beer tends to be very forgiving, and off flavors can have a tendency to fade away with time. I'm sure yours will turn out fine.
My batch seemed good to go as soon as it carbed. I did leave it in the primary for 3...
6 gal post-boil. You could scale the recipe down, or buy a bigger kettle. I've recommended to anyone who has asked me to go with a 10+ gal kettle. Even if you don't do gigantic beers, having that much headroom is nice :)