Sometimes it works and sometimes it doesn't. I find I have greater success when I'm making an offer on several of the seller's coins as a package deal.
I've done something similar to this. I contacted the seller and let that person know what it was and what it goes for (showed previous sold prices on eBay via Advanced search), told the seller I didn't want to wait for the auction to end since I'm impatient (character flaw, can't help it...), and asked if the seller would accept a higher BIN price to end the listing and I won.
Thanks for sharing your experiences on this subject. My first thought with high BIN's is the seller paid way too much for it. I understand them not wanting to lose too much, but if they want to sell the coin, they have to realize they're going to take some loss. In the other scenario you pointed out, I just don't understand the sellers mindset in that case. Why not get some profit for it rather than endlessly relist it. I've been in sales/marketing (business to business) most of my career, 30 years or so, and we have a saying as a reminder: Pigs get fat, Hogs get slaughtered.
The real answer, jp, is that most coin people aren't business people. It is a law of behavioral economics that people are highly reticent to take a loss, even if the short term loss would free up their money for a long term gain. The pain of the loss now outweighs the pleasure of the gain later.
In my humble opinion if the seller does not have or best offer he is being quite clear look else were for an auction or seller with obo. I have noticed a lot of over priced coins being re-listed you could put a watch on it and see if he/she lowers the price.