The ever lasting diamond stylus...is it a myth or??

Awhile back when my Clearaudio Gamma S had about 3000 hours on it I sent it to Germany and asked them to re-tip it as I assumed it was nearing the end.. They sent it back and told me that it was fine and to only worry about it when it started to mis-track. Considering that I had given them the go ahead to tip it and they did not and given that they have all the right equipment to check it, I can safely assume that they were correct. They did however ask what I was using to clean it as the tip was very gummed up. I had been using LAST. I switched to Clearaudio elixir as I figured that if they know how to make a $15,000.00 stylus, they must know how to clean it!

So.. I ended up selling my Gamma for a good amount of money considering it was used and bought a Clearaudio Victory H. I keep my records clean with a VPI, my tip with the Elixir and.. importantly, I think, I pay attention on how I drop the cartridge into the groove. I don't just drop the que but lower it gently into the lead in groove trying to avoid any sudden hard snap thus hoping to extend the life of the cantilever as well. I have had this cartridge  for about 5 yrs now with maybe 2000 hrs of use and have not heard any anomalies in playback as of yet. Letting your ears tell you what is going on with your cartridge may well be a good bet. 

One side of one average album is ~one mile distance.

According to the Wikipedia article about the LP record, 

The average LP has about 1,500 feet (460 m or about a third of a mile) of groove on each side.

So both sides of a record combine to make about 2/3 of a mile of grooviness.

I'd read that 1400-1500' figure other places as well.

Phono diamonds are man made, not the natural ones you find in most engagement rings.....  not nearly the same quality.  If indeed they are man made, can they really be called diamond...or diamond-like.

I can't tell if a diamond is worn using a 20X loupe. I was thinking of getting a 5 MP, 20-300X digital scope; but a totally gonzo cartridge/stylus photographer and re-builder on another forum posted that you need a combination of microscope and camera optics to get sufficient depth of field to see wear.

For $50 bucks, I may still try it if I get a new stylus for my MM. Then I'd compare old and new and see if I waited too long or long enough. Since the process is soooo gradual; I don't trust my aging ears.

I will say that I have a Shure V15RS with the original HE stylus from 20 years ago. I bought 2 new JICO styli, a SAS and an xMR. The HE and MR sound somewhat comparable, with the HE being stronger on the low end and the MR on the high end. Shape or wear??? I dunno; but I use the HE on older LPs with more surface noise. It is more forgiving and I figure the damage is done already.