Thanks for the analysis, @
mtseymour.
We would have to leave our ego at home to go with anything less than 4.7 (52-11). We originally only had a 12 highest gear cog on the cassette and would get dropped by single bikes because we were spun out. We like to ride fast downhill so 4.7 is a must. Plus, those single cyclists depend on us to pull fast on the downhill (we are too light to rely on weight).
It's sort of amusing to think we like >12% grades. I suppose we do in a masochistic sort of way, but reality is that these grades are a part of the every-day rides that we do. 15% is not at all unusual.
I think a triple is necessary for us for the best resolution in shifting.
I do like the idea of keeping our FSA cranks as I've looked at the others and too many drawbacks as far as I can tell (questionable BB with Lightning and I'm no fan of proprietary gear; old-fashioned looking cranks with daVinci though I would seriously consider them as I actually don't mind square taper axle and weight seems good; what's with Middleburn's website?? what little I can find on them is not impressive.)
Perhaps you need to work on a higher cadence. 50x11 army 120 rpm is 43 mph.
Above that kind of speed, it's typically more efficient to tuck and coast. Hammer the 50x11 at the top, then take advantage of the momentum and you should be plenty fast with a 50x11