I think the main problem is that often people don't realise which armours take the dye well and which don't. Black dye means research people! There are lots of pages out there showing dye on the different armour for the characters.
I sympathise with the OP though. I got a black dye drop in pre sear with my first chara and - not knowing it was rare - dyed her ascalon top. I still have it.
I think we should have a special 'rage page' in the forums for people to vent their frustrations in!
