Pissing off credit card customers with authorization charges
 

This question is for those who have their own processing systems. As you know some customers try to complete a pay form a few times before they get it right. Each time their payment is rejected they get an authorization charge that doesn't go away for a couple of days.

So, if they try a few times and then see $200+ worth of charges on their statement thinking those are real charges - how do you deal or go around that?

The software needs to not do that. Server-side form validation needs to be completed *before* the card authorization is run. If there is a problem with the form entries, the user should be returned to the form without any authorizations executed. Only after all other inputs are validated (including an algorithmic check of the cc number), then you do the authorization.