Those tests are on a 17c rim. Your heds are 19c iirc. Also, their drum must not be rough enough to mimic real world conditions as the data never shows the inflection point that silca blogged about.

Personally, I rode 20c SuperSonics on HED Jet + rims last year @ 90-95 psi depending on the road surface.

I'm your weight and I ride 80-85 PSI on those rims. I haven't had any flats at those pressures.
Without testing I would pick a low crr tire (which you did) and the pressure that keeps the tire with as small as possible in relation to the max width of the Jet+ rim (25mm). In other words... maximize aerodynamics (coefficient of drag x frontal area a.k.a. CdA).

I measured the mounted widths Conti 4000s II 23c, Conti SS 23c and Conti SS 20c and the Conti SS 20c is the only one that stays under 25mm at 80,85 and 90 PSI. For example, the 23c SS will go to 26mm when inflated at 90 PSI. Now... Conti SS has a smooth tread vs a textured one on the 4000s. The texture of the 4000s improves aerodynamics (Cd) but I'll gamble and say that the lower crr of the SS and the smaller mounted width (smaller frontal area) is enough to beat the aero advantage of the textured profile. That said I'm racing a Conti SS 23c in the rear and a Conti SS20c in the front at 85PSI.

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What's your CdA?

The pressure limits on this rim are all about keeping the tire from blowing off of the rim. By the traditional ETRTO a bead width this wide can't be used with tires narrower than 28mm, so to use them with narrower tires. Due to the tire shape being more U like, the air pressure can't hold the tire on the rim in the same way as when the tire is more round, so blowoff risk increases. Using a tubeless tire helps as they are more tightly tolerance and have non stretching beads, but I still would not exceed the pressure recommendations.

Having said that, 90psi in that tire on this rim is fine for your weight. The BicycleRollingResistance testing doesn't take impedance effects into account, so their machine would show even lower rolling resistance at 200psi than at 120 and we know that's not real. On a really smooth, hard surfaces with minimal surface voiding (like concrete or exceptionally high quality asphalt) you would benefit from more than 90psi, but honestly at your weight assuming average road quality, 90 is probably just about right, especially if you remember that the penalty of being too high is greater than the penalty of being too low.

For example, we tested that tire on a 19mm bead width rim on our 30 year old concrete velodrome which is a very hard, smoother than asphalt surface but a bit wavy and has expansion cuts in the concrete. We found optimal pressure to be 115psi for a 165lb rider on 20lb pursuit bike, but the difference between 90 and 115psi was only 1.5 watts. At 130psi the penalty was 1 watt.

Best
Josh

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To add to Josh's point. You most likely are not racing on smooth concrete, you are racing on torn up asphalt which is quite rough. 80 psi might be the optimal PSI for you. Josh didn't include a link to some of his relevant pieces but here is one recently they did simulating cobbles and the optimum pressure in that situation. In the higher PSI is faster camp, a good way to think about this is why don't mountain bikers want to ride 120 PSI? Instead they run as low as 20 PSI?

https://blog.silca.cc/...ressure-optimization

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