I agree with both of you, to a certain extent.
Quadruppel is a beer in which it's possible to go a bit too nuts with ingredients. I like it simple, even though all the ingredients listed are appropriate, as DB says.
The best Quad I've ever tasted was brewed from a pretty much even mix of Pale, Vienna and Munich malts (~28% each), with some Special B (5%, no more) for color and flavor. About 10% of the fermentables came from liquid invert sugar. Fermented with Wyeast 3787 to the tune of 12+% ABV.
Two additions are all you need, of Styrian Goldings and Saazer (bittering and flavor, respectively), just on the malty side of balanced. Don't waste your time and hops on an aroma addition. By the time this beer is properly aged, the carefully-added hops aromas will have completely dissipated.
As long as you're properly mashing, you really don't need foam-enhancing grains. I've never once had a problem with foam in a beer containing Munich or Vienna, much less both in the proportions I suggest. Besides, if you're aging this beer properly - like a year
- by the time it gets to the brandy snifter the last thing you want is too much foam.