The USTA computer system is a joke. The system is even more exaggerated in mixed where the computer has an even harder time crunching the different ratings between men and women.
There also seems to be a log jam in the 4.0 rating. Our 4.0 team had 5 players with a combined 1 loss. 3 of these got bumped up at the ESR to 4.5. But one player who got bumped last year at the ESR only to get moved back down at the YER went 11-1 with only one three set match and stayed a 4.0. I was 9-0 with a couple three setters, but the rest were straight set blowouts of good to decent 4.0 opponants and I didn't get bumped at the ESR. At the same time there was a huge influx of 4.0 ESR's from the 3.5 local league. Including one guy that was a self rated 3.5 who went 1-2 and got bumped to 4.0 . So basically we have way more people getting bumped to 4.0 than are getting bumped to 4.5, its like a giant 4.0 vacuum.
We still have districts, so this could very well change at the year end rating with a good showing there but I could not imagine playing 4.0 again next year. There are enough sandbagging/ringer comments this year and honestly this 4.0 season was a bit boring and each win became more of a relief than excitement because you know you shouldn't lose.
Oh well, enough with my almost daily rant of how bad the rating system is...