One of the more obscure aspects about the excessive chargeback programs at the major card associations is what happens if you don't find your way below the 1% limit. If a merchant acquirer decides to terminate your account because of excessive chargebacks, they may be required to place you into a file called the MATCH/Terminated Merchant File (TMF) list.
I've seen this happen once or twice, and it's basically the worst-case scenario. Whenever you apply for a merchant account, the acquirer is required to check that list. If you are in there, and you somehow manage to get approved for an account, you will usually be designated a high risk merchant, which means that you lose a number of rights around things like dispute, and more importantly, interchange qualification. You'll likely have to pay over 5% to process!
Here's a page that describes the list and criteria for the list in greater depth: http://www.findmerchant.com/merchant/merchant_tmf_file.htm
