Asrock sabotages its own motherboards with RAM slot sticker

Can someone elaborate for me on the "memory training" responsible for the long initial boot times the sticker warns about?

I skimmed this https://www.asset-intertech.com/resources/blog/2014/11/memor... and it sounds like a crutch for marginal silicon. How's it compare to Memtest86 and the like?

That's something I'd remember next time I'm looking at motherboards.

It's called a manual! Print it and read it!

They failed the execution but the idea itself is good. If ot males it easier to setup a new computer I'm all for it.