Well for me it's not about "permission," but buying a new headphone is an investment, and if I don't like it and end up selling it I lose some money. So if I can't hear it in person, at least it would be useful to read other people's reviews, and while graphs obviously don't tell the whole story, at least I can see whether it's the kind of sound signature I would want.
Quite right, and I wasn't referring to you when I made that comment. I just think we all have different tastes and different criteria for what constitutes a good headphone sound. Many of the headphones I ended up loving in the long term were panned by the so called "experts", who probably listened for a couple of hours at most, then moved on to the next item on the agenda.