This is my experience with the 3 Week diet.
Initially, I was doing very well with it. 2 - 3 sales a day, and sometimes a lot more. Got credited for sales, upsells, re-bills, you name it. Over time though, I noticed I was still getting credited for sales (granted, the numbers were going down fast), but I had stopped receiving re-bills under the vendor "3weekdiet" crediting me with my commission. Instead, I was seeing re-bills with the vendor "wvmedia35". Remember, I was getting re-bills VERY consistently and they stopped all together. Keep in mind, I never ever sent traffic to a vendor "wvmedia35".
This is what I see now. I haven't sent any traffic to clickbank in quite a few months, yet these guys are still making money off my traffic. I asked the 3 week diet vendor what was up with this, and he basically told me that he has a partnership with that particular vendor and that those are his sales, not his. But how come I haven't received a single re-bill commission in over a year with the 3 week diet, when before I was getting them (almost) daily?
I suspect that in order to stop having to pay affiliates for certain re-bills and upsells, the 3 week diet vendor partnered up with the other vendor in order to move the money elsewhere, thus avoiding having to pay affiliates while still being within Clickbanks' guidelines. Maybe someone can explain this. All I know is that I was being credited for re-bills like crazy in the past, and now they are completely gone. I did contact support about this and they told me the same thing.