In a former life I led some psychology research. An interesting study examined the expectation effects of technology. In a double-blind protocol participants completed the performance trials in one of four conditions based around both the quality and the informed expectation of a piece of sports kit.
1. Told high quality given high quality
2. Told high quality given low quality
3. Told low quality given high quality
4. Told low quality given low quality
Guess what was the major predictor of both quantative performance and qualitative perception? OK, it wasn't Nobel Prize-winning stuff by any means, but in 20-years of conducting this type of research we nearly alwasy found the same thing; if someone is told that the piece of kit (or drug) they're using is of certain quality, all other things being equal (or in this study, being deliberately unequal) they are more likely to perform in line with that expectation.
Call it the power of suggestion, snake oil, placebo effect, cognitive dissonance, whatever you want, but as soon as you have an expectation of a piece of kit, whether golf club or double bass bow, the way you use it changes in line with that expectation. I've seen people pick up a pre-CBS Fender as if it was a religious artefact, and play it with a tangible sense of awe and deference no doubt aware that an instrument of such quality will pick up and amplify every nuance of their technique. They pick up a Squier on the other hand.....