I need to pick between A and B but I can't hear a difference is the worst type of thread.

I hope you realize that while I do think these threads border on absurd, I'm asking the question tongue in cheek. 

There's a whole other forum set up for you to make comments about member's mental state.

Maybe they are soliciting advice on what to listen for between the two specific components, in the normally vague audiophile language of course. Sometimes you just can’t find Waldo on your own until someone points him out. Then it’s obvious. Even if they really are sonically practically indistinguishable there might be service issues, compatibility issues, reliability issues, or price considerations.

it’s usually not about you. But I’m sure if you ask nicely someone can line up a barrage of asshat questions specifically directed at you. 

To me, I get kind of a kick out of it when a person that can't hear a difference between a couple of components asks this august body which of the two to buy.  I mean, the answer is easy.   Buy the cheaper one!