What is your experience with the law of diminishing returns ?

I will give an example within my current system. Power cords, yes again. One is Purist Dominus used to have $2100 retail price, another Top Gun by CPCC used to cost $800.
If I compare them on the integrated amp the sound difference is big enough to justify the price difference, but if I compare them on either phono stage or cd player, it is not. For me. Dominus is still better in every respect everywhere. Sound difference on regenerator also would justify the price difference.
Since I bought them both used, for $120 and $650, I would put Dominus everywhere if I could find more of them for that price.

Law of diminishing returns is a real measure of value. You cannot get value in the remainder. If you don’t care about money, go ahead and spend $500,000 or hit that glass ceiling. The rest of us are laughing all the way to the bank.  

In my case, my Bank laughs at me everytime I walk into it.....