There was a story in a High fidelity magazine that was similar, it was about a man who had a turntable that needed a new needle, and so he went to the store and bought the very most expensive diamond stylus they had.
He took it home and called a friend who was good with electronics to help him install it, when the friend arrived he showed him the new stylus explaining how it was the most advanced and expensive available, then his friend said he would start work installing it, so the owner went in the kitchen to get some drinks for them.He was still in the kitchen when he heard his favorite record start playing, and he noticed right away that it seemed to sound better than it ever had before, he ran in the living room where it was playing , and was immediately stunned by the glorious sound coming from his stereo, never before had he heard such lush and full sound from his stereo,he said that it never sounded so good with the old stylus and it was well worth the extra he paid for it.
His friend said when he examined the turntable there was nothing wrong with the old needle and all he did was connect a broken connection , and that it was the same needle they had always enjoyed before.
This happens all the time with pro recording artist too, they will ask for a change in the mix and before you can do anything, they think it is better because you already fixed it.
It is also why when testing new drugs for effectiveness against health problems, the doctors all use double blind guidelines where neither doctor or patient knows who is getting the placebo and who is getting the real drug. In the past when this was not the standard , new drugs were given much more favorable ratings , only because the patient was getting the placebo effect, where one thinks it is better based on the hype and hope of a new drug that will cure him.