losing money due to receiving bad Bitcoin is nothing qualitatively new. I'm not saying it is a good thing though.
"Bad Bitcoin"? Wtf... I know you have some Monero to sell but this is beyond ridiculous
It took me a second, but I now appreciate the #bitcoin-assets '
there are no tainted Bitcoins, only tainted institutions' POV.
I love the smugness of that serene maxim, and look forward to the day when it has practical value for those of us with <100 BTC.
OTOH, I believe (smooth will have to back me up with The Science) that Bitcoins are not perfectly fungible at the protocol level because they are uniquely identifiable, and thus may be discriminated against (ie, considered "bad") by individuals, if not in the aggregate.
AFAIK, the Monero protocol couldn't tell "good" coins from "bad" ones even if it wanted to, so its coins are perfectly fungible (no matter what, and without need to invoke rosy assumptions about the future of crypto vs fiat).
Bitcoin Black/Whitelists: technically trivial to implement and enforce, commonly done in status quo (eg stolen Evolution coins at BTCE)
Monero Black/Whitelists: technically impossible to implement or enforce (is it true?)
I still don't see how that holds true.
As smooth himself has pointed out, once two satoshis are spent from two different inputs to the same output they are indistinguishable.