Last weekend, I did a tt and it was WINDY. I ran a disc and a 90mm front because I didn't think to bring some lower profile wheels. Rode super conservative just to keep it on the road with the rubber down, and came to a disappointing finish.
So here is the question: What do you think is the optimal wheelset as a function of wind speed? For the sake of the discussion, lets assume a flat course so weight isn't as much of a concern. Lets also assume some sort of circular or box course so will experience wind from all directions.
I'll run the deep front - disc combo in most flat to rolling time trials as long as the wind is fairly steady and not ridiculously strong. But like you I've had trouble on days with strong gusty winds and am pretty sure whatever the deep wheels offered in terms of aerodynamics was lost by having to focus so hard to keep the bike on the road. It can be a real wrestling match on really gusty high wind days.
The best solution I've found is to run 50mm deep rims front and back on high wind/gusty days and run my deeper (95mm) front, disc combo on less gusty and low wind days. The 50mm rims are also my general road racing rims and light enough for most hill climb events or mixed terrain time trials with substantial climbing. I still feel the big gusts with the 50mm rims but they're not nearly as disturbing and a lot easier to keep under control and overall I'm convinced they help me go faster on gusty days.
Well, it really does depend on how you define optimal. When you say optimal I think more along the lines of versatility. I'll bet that a 40-50mm depth range will be much more practical for everyday use. It will still be quite aerodynamic straight on but where that depth will really excel is from the side. The yaw angle tolerances are much greater on a shallower rim which will make the ride feel much more stable and predictable particularly when dealing with crosswinds.
