Lets assume this is a Honda. So...
-Factory parts are of consistent good quality
-Factory settings are well defined and work well

Meaning that any brand new S2000 has a pretty consistent potential clutch life.

If a robot were driving them in a controlled environment, they'd all fail at around the same time.

Yeah?

Yeah.

The variable here is you people.

Foot resters: MF's that will wear out a clutch by driving with their foot on the pedal. Depending on body type and driving position, the effect of this can be different.

Farmers: MF's that drive tractors and diagnose a perfectly good S2000 clutch as "bad" because it doesn't engage right off the floor like it does on their tractor.

Racer #1's: MF's who launch, take part in track days, etc. People have different styles and abilities. So they will affect the clutches at different rates.

City slickers: MF's that drive in stop/go traffic. some are better than others. some use half the clutch every time they start.

Hill billies: MF's whose every start is on a steep hill.

Engine breakers: MF's always downshifting for every light.

and about a million other factors.

Plus driving environment. Dust, heat, water, snow, etc.

There's not going to be an accurate way to tell how long anyone's clutch will last.

People also diagnose what's "bad" at different stages.

OP's clutch "feels weird". From where I'm sitting, everything feels just fine.

Maybe at 50K of typical use, the clutch isn't worn. But if you launch and bang thru gears, you notice a little slip. Some people will replace the clutch at this point so they can get that crispness back.

Diagnosis is key.

 

For what its worth, I had a very low mileage ap1 before the car I have now. The clutch started acting up - sticking to the floor, roughness through the stroke, and the like. I am convinced that the grease on the throw out bearing and the guide had dried up likely from lack of use, not for poor driving technique. I got in there a bit and put in some well placed grease and it improved. I sold the car for other reasons with full disclosure. But I am convinced that the clutch itself was fine but whole thing was going to have to come out anyway to relube/replace the release bearing and the guide.

 

I replaced my clutch recently 110k miles. Not because it was slipping, the original throw out bearing caused vibration on my clutch pedal which made a lot of noise. It feels great now having new bearings and grease. It took me around 10 hours at home, split in two days with a help from son. I am not sure I could have done it alone as the transmission is quite difficult to move around when the car is on jack stands.

 

"I'm not really sure why anyone feels the clutch needs periodic adjustment.

Its adjusted from the factory.

The pedal engagement should stay the same until the clutch has worn past its workable limit.

You shouldn't be adjusting for wear.

Like...you wouldn't top off brake fluid to account for pad wear.
I hope...."

Well, there is a big difference between a brake system and the clutch. Brakes are designed to self adjust. The pistons in each caliper change position as the pads wear. That's why you have to drain brake fluid when the pads are replaced and I do hope that you add additional brake fluid as the pads wear.

 

...the clutch also self adjusts

The throwout bearing is preloaded against the pressure plate always. Right?

The pressure plate is also preloaded when you tighten all the bolts.

As the disc/pp/flywheel wears, the space is taken up by loss of preload.

If you manage to wear the clutch to the point where that preload is lost...then its completely fried. Adjusting it to work in that conditon is a bad idea. Its time to replace the clutch. Not adjust it.

You may need to adjust the pedal when you replace the clutch to make up for manufacturing tolerances of the new clutch kit. But...you shouldn't need to adjust the clutch thru its whole lifespan.

And the brake fluid thing was a point to illustrate that you don't compensate for wear. Also....no...lol, you shouldn't top off brake fluid. The master cylinder level goes down as the pads wear. Once the "BRAKE" light comes on due to level...its also an indication that your pads are totally worn. So...why would you add fluid to the reservoir?

 

You'll know when it's time to replace the clutch due to wear. Signs that it's time might be slipping or trouble shifting gears, but consistently - not once in a random while. I've ha six MT cars in my life, all with no less than 125K and only one needing replacement was my TSX at 225K (the others didn't make it past 125K in my ownership). Granted, I don't drive hard - and all but the S2K were a lot of highway miles.

But to answer your question, no - it's not something you change proactively. It's major surgery and you do it when you need to. A stock Honda clutch very likely will never leave you stranded. Change it with another Honda OEM clutch when it's time and have it done by a reputable shop that has worked on S2Ks. The shop guys that said it felt "weird" should not be touching these cars.

 

You never need to drain fluid when you swap brake pads. Why? Because there is zero reason to add brake fluid as the pads wear. None at all. The reservoir is designed to contain enough fluid to to work properly until the pads are gone, hence the big range between low and full. All production cars are designed this way. Think of this this way, do you think the average driver looks at this? Nope. A mfgr is not going to design a critical system like brakes so that fluid falls dangerously low within the service life of the pads or you would have people crashing due to loss of brake pressure every day.

 

Honest question. When you change brake fluid, do you personally:

Note fluid level in reservoir, and make sure its same level when you're done?

Only change fluid when you change all pads, so topping off fluid coincides with fresh pads?

Top off fluid, then just deal with extra reservoir fluid when pads changed?

 

On the s2k, I change fluid each season because I track it. So I try to align that with a pad change to keep things simple (since I go through multiple sets of pads per season, a pad change is typically not too far away). On all my other cars, fluid changes are obviously much much farther apart. In those cases I just put it back close to where it started.

 

With any car, I do a fluid change at the time I do pads when it's due for a fluid change. I usually get two sets of pads to one fluid change, so for the in between pad change, I leave the fluid where it is so that when I compress the pistons the fluid returns to the normal high mark level. Adding fluid as the pads wear down just means you will likely overflow the reservoir when you compress them, unless you open the bleeder. Regardless, as they wear, keep an eye on the fluid level from time to time. When you do the pads and fluid at the same time, you just top it off to the high mark when you are done and you know you are all set.

I did a gravity bleed to change it the last time using Billman's process and it worked great - took a long time but I didn't need to deal with bleeding them.