It is not exactly placebo. If you know that something is there then obviously it is easier to expect this.
Agree, I thought about editing out the word Placebo too but didn't bother in the end because either way I thought it reinforced my belief that subjective reviews are highly subjective, to be ignored or best taken with a grain of salt. It is more like expectation bias in this case as KR himself alluded to.
Hearing and smell feeling is so deep into our brains that if you suddenly hear something, i woud rather trust that rather than try to find some pseudo psychological placebo explanation to that.
That, I must disagree, but perhaps I misunderstood your point. To me, KR made it quite clear in simple language that what he thought missing was there all along. He repeated the same observation later on in the review, when listening to a different piece.
It didn't surprise me at all because it happened to me too, more than once. The first time I added an Adcom amp to my AVR I thought there was an obvious improvement in bass and transparency overall. Same thing happen when I substituted it with my 4B SST. Later on when I went back to do more lengthy AB comparison sessions, without the often recommended volume match to 0.1 dB, I found out the difference I heard was due to expectation bias. The expectation probably came from the fact that I know the amps have superior specs on paper, and the huge difference in price between the devices being compared and I had read many subjective rave reviews of the Adcom and Bryston amps prior. After that, expectation bias did not have the same effects on me any more. When I acquired the Halo amp, NAD, Cambridge Audio, Anthem, Marantz etc., and now the $240 QSC amp, I did not anticipate hearing details that I haven't heard before, the expectation bias sort of started to work in reverse order
. Anyway, we can agree to disagree, I am just sharing my personal experience though I should mention that some of the comparison sessions were done in the presence of others, and there was consensus so I know it wasn't just me.