Let's talk power cords

"Lousey (sic) observations are of no consequence to scientists - it is why we do CONTROLLED experiments...."

A necessary underlying assumption being: suitable experimental methodology exists.

Controlled experimentation is not the sole and exclusive avenue by which valid observations are made. Observations in uncontrolled settings are often made first and subsequently drive experimentation under controlled conditions to validate and understand such. Lack of an immediately applicable experimental method does not invalidate the initial observation(s).

Discussion with personalities prepared to discount experiential data from all others contradicting their opinion is pointless.

On topic - I've assembled my own power cords with great results using oyaide tunami cable & neotec connectors. 
Off Topic - Willemj, I want to thank you for reminding me on another thread (you've been hitting the wire topic pretty hard lately) that I needed to replace the coax cable between my DAC & transport. I did that this week. It isn't broke in yet but sounds great. 

experiential confirmation bias

Good thing you are not allowed near drug development labs

Not only power cables make a difference, also the IEC connector in particular and other connectors in the line, fuses if you use them, dedicated spurs and consumer units all have an effect on SQ.

Jond,
I am busy right now but I shall try to dig up the details. What it amounts to is that the law in most EU countries in one way or another does not allow deception in sales. Here was a chain of audio stores that claimed that the cables they were selling were sonically superior. So the UK Consumer Protection Agency (I think it was them) took the stores to court because they could not prove that claim. I think expert witnesses were also called in.
Other groups could have done the same, like consumer organizations (they often do) or consumer tv programs that name and shame.
The store had to withdraw its claim, and without that claim there was little point in selling such expensive cables. Unfortunately this does not mean that things like this will not happen again, and many cases may remain under the radar, but it does mean that sellers have to be very careful with what they claim.