moTi - 10:56 am on Jul 3, 2006 (gmt 0)

One fraudulent advertiser cannot bring down an entire business model.

it's not about bringing down the entire business model, but the extent of damage which can be done per single participant.

I get the feeling that the existence of CPA makes you nervous.

cpa already exists since the start of affiliate advertising. it's just that cpa is a seriously flawed accounting method for the reasons given.
whereas you seem to massively support your own (affiliate business) interests, i merely want to express my (publisher) concerns regarding an adsense cpa pricing model. i think this is perfectly legitimate, whereas it seems you have some problems in comprehending the reasons for the arising dispute.