Not familiar with this specific climb, but I like to have a 1:1 gearing ratio (for me 34x34) for the really steep stuff. If that's not a low enough gear, than I'm just not trying hard enough. YMMV.
I find that if I use a triple, and drop into the granny gear, all that happens is that my spinning rate increases, and my speed goes way down. There's something about pedalling such a tiny ring that seems inefficient. And I really don't feel any better. But hey, for the couple of grams a granny ring weighs, why not have one just in case?