For quite some time Sedo has been setting a linear trend downward about 4 days after a domain has been first added. Has this happened to you?

Absolutely! It also happens as soon as a domain has a big day (revenue spike) as well, eg you change a keyword and the CTR or the EPC changes dramatically OR the name is a seasonal/cyclic one and it's cycle causes a huge increase in traffic for a day or two. As soon as this spike hits you inevitably see the revenue get tamped down over the next few days as the EPC drops to bring it back to where it was before with the old keyword.

We've only started analyzing sedo revenues now but there is definitely a downward trend evident on the portfolio level. I can confirm that sedo screw you've posted about but it's not uniform.

I have had access to view a few portfolios now that should have similar patterns as they're very similar in sample set. One of them is clearly decreasing in that screw, the other it is less evident.

Interesting, do you have any definitive stats as yet?

Nothing yet, it'll probably be a few months before we have anything intelligent to add.

first, sedo uses a "clever" algorithm to calculate EPC, since it does so real-time, but gets real EPC from G only in 24-48 hours. therefore, sedo bases EPC calculations on historical data. when we see EPC rise, it is like a light of a distant star, this rise could have happened ages ago.. =) (48 hours it's ages in virtual world).

secondly, sedo has a cap on EPC, which is 7.51 or something for normal PRO accounts and a bit more if you're on a bonus deal.

Yes, you're right. All Google based parking companies have to guess the EPC for 24-48 hours. Where did you get the capping values from? Experience or did someone in Sedo confirm the numbers?

Obviously Sedo will not confirm it. All numbers are derived from my own 2+ years experience.
Overall it feels like a "cake and scourge" experience, comparing to many other parking companies.