From the perspective of an ebay buyer, but rarely a seller, and collecting novice:
Seems like stated intent of initial post in this thread was to get some feedback as to whether seller was being reasonable. Also seems like the actual problem was the buyer made some kind of error checking out and missing out on one of two discounts actually being offered. The rest of the stuff about wanting additional discounts, etc. doesn't seem to have been what caused the dispute (as irritating as it may have been ).
So the dispute comes down to --buyer wanted the two discounts seller actually offered, but made an error checking out. Seller apparently offered a compromise so buyer would get part of the extra second discount, but not the whole thing.
As an ebay buyer, I have had sellers who allowed me to retract an erroneous bid, and I have also had sellers who refused, leaving me with something I didn't want. I leave positive feedback for those who assist me. I don't leave negative feedback for those who don't, since I recognize I'm the idiot who didn't read the description carefully, or clicked in the wrong place, and I know I am responsible for following through with any bid I make. Though it is aggravating to get stuck with something I didn't want. (So far it's only been inexpensive items).
So the guy was way way out of line for negative feedback about a seller who actually worked with him, and who didn't do anything wrong. But as a buyer, I'd be annoyed if I clicked on the wrong button and missed out on a discount, and would think the seller should have given me what was offered. I probably wouldn't be keeping that seller on my saved seller list.
So that's my long winded two cents worth
