Yeah...It does not come cheap but it sure does a good job at reducing friction. By extension it will also reduce wear so it kind of pays for itself really.
Further to Rick's noisy DT240 freehub (DT wants you to use their proprietary grease for that, IIRC), I once had a Campa Bora Ultra set which had some slightly off standard size pawls.
They were only longer by a few microns but made a hellish racket once you stopped pedalling. They did a great job as a bell though.
A noisy freewheel does slow you down though so, eventually, I did replace the pawls and all was back to normal.
Ever noticed how professional always seem to pedal? They hardly ever stop pedalling, do they?
I wonder if they're actulaly aware of the fact that it slows them down. Just something I wonder.
While we're at an anecdotal level, I first found out about Krytox through a chain lube that had that particular additive in it.
I didn't like it as a chain lube as the hype was a bit misleading (as usual) but it did make me look up the properties of Krytox.
Since that product also contains wax, all it takes to separate that from the rest is to let it sink to the bottom of the bottle.
Once that was done, I decided to try the top part of the bottle's content out as a lube that would replace the grease in the USB Campa bearings. I was stunned to the point that I checked and checked again that this was really the cause of the improvementt. As it turned out it was.
I had run these babies on oil before and had noticed the difference between that and the otherwse excellent Campa grease but this was just a major step beyond. It felt as if all friction had vanished.
That being said, this is already relatively old tech as there are much better technologies available to reduce friction.
They're just starting to be applied now. Often more as a selling argument than a true and thoughtfully applied improvement but it's a start.
Reducing friction is like shedding weight. It makes you feel as if you ride a lighter bike.
Looking forward to your feedback,