Wait a second, did someone just compare camera lenses to car pistons?!?!
Yep, that is the kind of "reasoning" we have to try to dispel sometimes.
Not the best analogy maybe, but if you try to read what I said rather than trying to take one sentence out of context, you might understand. THERE IS METAL TO METAL CONTACT. Your reasoning is, there is not enough metal to metal contact to cause any "appreciable" wear. I say, there is certainly metal to metal contact that causes wear, when people rush to change lenses...as if they are changing wheels on an F1 racecar. Oops, there's another car analogy! My whole point was, the mount is far from indestructible, and care should be taken when changing lenses. If you are just wanting to argue, go ahead, but you have to admit, I have a point.
Hold on, let me post under another name to egg this on...oh wait, I'm above that.
And you are speculating that opinion from your own fantastical mind. I am saying I, personally, have had at least half a dozen cameras that have had thousands and thousands of lens changes and neither the lenses nor mounts showed any wear. You are now changing the point from "fast lens changes cause wear"
to a more subtle and easier to "prove" "metal to metal contact causes wear"
I have noticed this happens a lot on this forum, more so than others, people theorise about something, somebody with actual experience comes along and says your comments might be theoretically sound but your conclusions are off by a factor of, a lot. The theorist then goes on and on posting, giving meaningless comparisons, ever longer lists of calculations and percentages to "prove" their point, meanwhile the poster with actual experienced gets completely pissed off and either leaves the thread or annoys any readers by trying to defend their position which actually answered the point.
Take it or leave it Carl I am not your enemy, but on this point you are talking rubbish.