Quote from: AliceWonder on July 28, 2014, 06:08:38 PM

Quote from: RodeoX on July 28, 2014, 05:59:28 PM

Quote from: AliceWonder on July 28, 2014, 05:50:24 PM

Or in 40 to 70 minutes the merchant finds out you sent the same outputs to 4 other addresses... and the transaction you sent to him was not confirmed.

Equivalent of writing a bad check but he has nothing to go on to recover his losses.

True. it's a legit risk. I like using the number of confirmations relative to the amount as a way to mitigate the risk. So if I were selling a car I would want 6 confirmations. If selling a bag of popcorn, I might not even wait for one.

Selling a car you can wait, but the wait time at places like the grocery store where the cost is often several hundred dollars would kill the checkout. So the only way those places could accept bitcoin is through 3rd party, making bitcoin not the best coin for them. Other coins however have much lower risk.

With 30 second confirms at a grocery store there is much less time to try and pull a double spend so the risk of letting them leave before confirm is far less than with bitcoin. And if you do see a double spend hit the network before a confirm you may even be able to have your security record their license plate number because it would have to very quickly be executed.

There's no need to try performing a double spend, just steal the grocery bag, much easier. Better to keep the entire network safe by 10 min confirmation, instead of those altcoins with seconds of confirmation times just so that mommy/teller can see it's confirmed, but when she comes home, the entire thing has gone to shit.