[redial]

0-confirmation seems to be just a placeholder, so I do not think it is comparable at all to a credit card verification.

I do not want to nitpick but credit cards validate, that is to say they verify the parts in a transaction and resolve instantly if it can or cannot take place, and then it does take place instantly. That you can "take it back" is a feature independent of the actual operation. The settlement period is not a technological imposition but a human one; it is in place because humans are not trustworthy.

On Bitcoin on the other hand, the limitation is inherently technical. The protocol verification methods are slow by design.