YSM Blocked Domains: Hercules and the Hydra?

Yahoo recently introduced Blocked Domains, a feature within YSM whereby advertisers can block up to 250 domains from within Y!'s distribution network. All observers, myself included, are glad Yahoo's doing this as it shows their commitment to improving the quality of their search distribution network.

However, a one commenter on Webmasterworld noted today, for every crappy distribution partner he blocks, more pop up. 'Beren' writes:

Over the past six months or so, Yahoo seemed to be doing a better job getting rid of scam affiliates. There were still plenty of them, but after a complaint, the bad ones usually disappeared. There was always a rotation as the scammers just switch to other domains, but it seemed overall to be getting better.

Then in the summer YSM introduced Quality Based Pricing and things were even better. I started to think YSM was getting serious about quality control and giving a decent deal to advertisers.

Then they started allowing blocking of domains, and I hoped things would get even better. I put in the worst offenders on my list and waited. Immediately new affiliates sprang up. I put them on the list. New ones, more additions to the list. The rate of new YSM affiliates in my industry appears to have increased vastly in the past couple of weeks. It's like Hercules and the Hydra: cut off one head and two more spring up in its place.

I just wanted - for one day - to get the percentage of YSM clicks coming from yahoo.com to get as high as 35%. No matter how many affiliates I block that percentage doesn't change much.

One anecdote does not a trend make, but most people I've talked to on the AdSense/YPN publisher side have said they don't expect Blocked Domains to actually block crappy distribution partners.

Only time will tell, but let's hope for everyone's sake Yahoo does better than Hercules did with Hydra.