Den 7 aug 2015 23:37 skrev "Sergio Demian Lerner via bitcoin-dev" <bitcoin-dev@lists.linuxfoundation.org>:
>
> Mark,
> It took you 3 minutes to respond to my e-mail. And I responded to you 4 minutes later. If you had responded to me in 10 minutes, I would be of out the office and we wouldn't have this dialogue. So 5 minutes is a lot of time.
>
> Obviously this is not a technical response to the technical issues you argue. But "minutes" is a time scale we humans use to measure time very often.

But what's more likely to matter is seconds. What you need then is some variant of multisignature notaries (Greenaddress.it, lightning network), where the combination of economic incentives and legal liability gives you the assurance of doublespend protection from the time of publication of the transaction to the first block confirmation.