^ agree with all the above. As a side note, the validity of DBT for testing audiophile claims depends on the assumption the ear/brain system (EBS) is exactly like reliable and properly calibrated test equipment. Test equipment performance isn't affected by how a cable looks or the topology of an amp. Nor presumably does EBS performance vary under blind testing conditions. However, if under sighted conditions EBS performance varies then DBT is not as appropriate a methodology as it seems.
I guess the question becomes - if we all knew that the error margins of our EBS was greater than the sonic differences between a Parasound amp and a Krell amp, or a $500 amp and a $5000 amp, then would our purchasing behaviors be different? For some people, I imagine not. For others, I imagine yes. And thereby, people would still be able to follow their preferences, but would be able to make a slightly more informed decision.
Let me say that I dont actually think every bit of equipment necessarily needs to DBTed. I dont know if anyone here remembers Arny Kruger, a big proponent of ABX testing from the 90s, but that DBT-uber-alles mindset leads to such a sordid mindset that sucks the life out of enjoying music. "Verify or STFU" is a needlessly antagonistic and excessive position to take.
However, I think the industry would do well to test atleast a few of the more debatable concepts - cables, burn in (Ty's article - excellent start!), high-res audio, etc. At the very least, this lets people put into context some of the non-verifiable claims being made on Head-Fi (especially when the EBS is so prone to confirmation bias and where often-repeated beliefs become dogma as a result).
SET amps can be reliably differentiated from solid state in DBT. The tubilicious sound is no placebo effect; it's real and audible.
EDIT: I'll add that DBT doesn't answer "which is better" or "which is more realistic". It doesn't express judgment or preference.
It only answers, "Can you tell these apart based purely on listening with no other clues."
Sorry - I dont think i was clear in my earlier post. My reference to SETs was to make the point was that I am strongly in the "listen to whatever you prefer" camp, and so am definitely inclined to support your point that everyone should listen to whatever makes them happy, even if it is placebo.
Love the word "tubilicious" btw. :)