While I agree that differences in MOI are insignificant in almost all cases, the topic of MOI in bicycle wheels isn't junk science, rather it's misunderstood science. By misunderstood, I mean that people forget to also look at the context of those differential values. For a racer, whether he/she is pro or not, it may well be worth it to get those lower MOI wheels. When racing, it's normal to grab every advantage you can, even if that advantage is whisper thin. Junk science is stuff like Intelligent Design or all those inventions whose creators say run on perpetual energy.
Bike Companies exaggerate such parameters to create junk science. Ofcourse, today the average consumer doesn't have the time or energy to think a little about these things , and they're easily fallen to thinking top end CF wheels and frames are everything. Wrong.
I also think you're overstating the fragile nature of CF wheels. In fact, I don't think that fragile nature necessarily exists at all. As with any relatively new application for a material, there is always worry and doubt. CF wheels, however, have proven themselves to be quite durable. Granted, Zipp had an issue with some wheels, but after changing the layup on those wheels, the issue has been resolved.
CF is fragile, infact more brittle than glass and this becomes a bigger problem with HM and UHM fibres.
The bleeding edge does not mean that you have to accept a lower level of durability or less safety. If that is truly the case, then there is a designer/engineer doing a very poor job. In recent years, more bicycle companies have brought high level engineering and analysis to bear on their design process. As a result, the new, cutting edge products are becoming durable, as well as light. Sure, they're expensive, but that's to be expected of anything on the "bleeding edge."
A good designer can work around the challenges offered by materials. But how good is good? We don't see or know who designs the CF frame that we descend at 60 mph on... Infact, working with CF can be done by any fool, its really easy if you have the patience and time. Much easier than welding or brazing, and so gone are the times when you can get a good lugged frame that will last your life and costs not that much.
Besides, CF is expensive because its hard to acquire. Its expensive because the molds are expensive, and so on...
Today consumerism has taken a drastic turn and nothing we buy can last us 3-4 years, everything gets worthless or is outdated. So true in cycling. Bike companies are out to fool some of us with their junk science.
Reading through your blog, I think you make the mistake of generalizing about a material a few times. For instance, when you mention the CF impregnated rubber drive belt, you hint at decreased durability as a result of CF in the belt. However, Harley Davidson's drive belts, made the same way, set a new standard for durability....which is quite a change for that company.
Use of belt depends on the application. In some areas, it works better than others. I don't think Harley Davidson has 3 rings up front and 10 cogs in the rear, a good old roller chain that has been around for 100+ years does power transmission on such a mech better than anything else out there. Its efficiency is 96-98%. A CF belt has very little application in bicycles right now, in fact only practical in a single speed system.
Failures in the past, with CF products for cycling have largely been the result of poor design, poor engineering, and a poor understanding of a relatively new material. Sure there are still a few folks making CF stuff without a real good understanding of the material, and there are a few companies possibly cutting corners. Those cases though are the exceptions.
As with bicycle frames, it's best to not weigh the material something is constructed from too heavily. Material is far from the top of the list of important considerations in a good product.
You are right here. Design comes first, than materials. I'd probably buy a CF frame from a highly reputed company, but also think of the cost vs. benefit. With high end frames, everything in the design is optimised for performance and nothing beyond or below that since thats a wastage of resources, sacrifices performance and also ups the cost. Thats what I mean by bleeding edge, its on the edge, durability of such products is highly debatable.
Also, please don't run your tubies at 10psi under max inflation on descents/fast descents. Traction is your friend when corners come fast, and having an adequate contact patch insures that traction. Rolling tubies off the rim is the unusual case.
