Does anyone know the weight of one recipe of the WASC? I'm trying to figure out how much I'll need if I decide to go with this recipe. Thanks.

Using DH white cake mixes, a full recipe of Rebecca Sutterby's WASC cake yields a tad over 14 cups of batter.

Here's Rebecca's expanded WASC cake recipe:

http://tinyurl.com/2cu8s4

Filling your cake pans by batter weight rather than volume might not yield the results you desire.

Here are all four Wilton cake preparation and servings charts:
(Gives batter requirements by pan size, as well as recommended baking temps. and times - and more.)

http://www.wilton.com/cake/cakeprep/baking/times/index.cfm

HTH