In message , at 15:39:25 on Sun, 26 Feb
2012, Adam H. Kerman remarked:
My one step: Enter PIN which is checked, and terminal asks CCC
for auth for the exact amount, checking for stolen
cards, floor limits and available credit.
Their one step: [Usually] CCC sends auth to retailer's terminal, which
displays "accepted".

Does the retailer also receive a transaction ID number, a number that
also appears on the cardholder's monthly statement?

If so, then the procedure is comparable to what happens here.

UK credit card statements (including Amex) don't usually have
transaction numbers.

What I was disputing was your retailer "two pass model", with the card
itself being authorised up to some "reserved" amount, ahead of the
actual amount being claimed milliseconds later by the retailer. I don't
know why they'd do that, rather than ask for authorisation of the actual
amount first, because in the UK the amount has to be known before you
enter your PIN into the C&P device, as entering your PIN is an agreement
to pay that precise amount.

The two-pass scheme is used in other circumstances, such as checking
into a hotel, when they often "reserve" an estimate of the final bill,
ahead of the day you eventually check out.
--
Roland Perry