I scaled up to 3 gallons, with a few hitches. I tripled the fermentables and lactose. On WLP 001, I let the ale go for 1 month. I can't stand yeasty off flavors, that's why.
I racked to bottling and found a drop from 1.062 to 1.014. I will tell you, this version of the recipe really upsets brewing software for Beer Alchemy.
I tripled the honey & vanilla, left the priming sugar at 1 cup (which is too much for a 5 gal batch of normal beer, so I was a little reticent to use 3 cups), and went with 5 tablespoons of "old fashion home brew root beer extract" because LHBS didn't have McCormicks. I'm checking it tonight for carbonation (5 days in). We'll see...