An amazing thing has happened, in that acceptance of the idea (actually, the fact) that using one wheel versus another isn't going to affect your speed by 1mph or whatever, has seemed to spread really fast and with little resistance. This statement is created by too many data points to list each, but I will give this thread as the proxy. Until recently, threads like that seemed to go directly to wheels and then get deeper into it from there. And it's not that there are no differences, there are small gradations along the way and some deep wheels do offer aerodynamic benefit, but the days of anyone credibly claiming that switching from X wheel to Y wheel caused an immediate speed increase of Z mph sure seemed to end quickly.
So what next? I know that in my own thinking, tires and tubes or not tubes got even bigger than they were, and they had been a big deal already. Rolling resistance, comfort, cornering and grip - neglecting any of these is leaving performance on the table. But as we discussed recently, your personal calculus is going to be specific to your situation. A recent customer wanted to try tubeless and likes to go fast, but also commutes on his tires. As such, I recommended Padrones rather than Vittorias or Pro Ones. Not as outright fast as the "track day" type of tires that Vittorias or Pro Ones are, but plenty fast and more durable and (anecdotally, at least) more flat resistant. Since I've got a big race next month and am fat, old, weak, and slow, my particular X is that I'd sell my soul for some extra speed. I'm willing to risk the faster tire - and let no one ever think that I'm immune from these mind games we play with ourselves. I'm a head case with the best of them.
One area that always gets a lot of focus is weight. The physics show it as being not that big a deal at all in performance outcomes, at least to the level that cyclists like to think about it (a guy spit the dummy on a forum yesterday because some rim he'd gotten was 5g over stated weight), but it's so deeply lodged in our collective psyches that it's not coming out any time soon. Maybe because everyone has a scale, and can lift up a bike, and determine "that is, or that feels, light" and approve, yet wind tunnel results were never as primal or tangible and so people were always a little skeptical?
Anyhow, there are lots of rims out there that are vying for the light weight crown. Some claimants to the crown have been shown to be more ambitious than qualified but there are others out there that are really pressing the issue. For reasons which are beyond the scope of this post but which I promise to go into sometime, I'm ultra skeptical of how well these will work out. But in any case we're talking about 1300 to 1400g wheels. And that's light, but it's not that light.
On the other hand, it's easy to build a set of tubulars that are under 1200g and you can do it for pretty short money (under $1k). Again, reasons outside of this post but that will be addressed, I have misgivings there, but all the parts are basic and readily available and have been in use for a time.
It's human nature to look for something, and I don't hold myself out of the fray on that one at all. Soon we will do a new post on Mike's new wheels which I'm borrowing for the rest of the spring, and you can see all about that. But it would shock me none if people all of a sudden got the collective realization that really light wheels are an easy trick to play if you are willing to go tubular.