I am seeing somewhat slower pages too, although not in the range of 45 to 60 seconds (more like 5-15). It happens at various times throughout the day, so I had put it down to my provider or even other processes running on the computer at the same time... I know there's a few more images being processed per page, but thought the cleaner code would have resulted in cancelling out that loss in speed.
I just look at it that the good things are worth waiting for - or something along those lines!
We had a crash last week and had to restart the server. I'm wondering if maybe this problem was per chance solved at the same time? Fingers crossed really, because we still don't really know what's causing it
I also added some additional caching to the site, which should speed up a few of the pages and slightly relieve the server to process others more quickly.
On this issue, we have taken the step of moving our database to a new server. Though there is still some work left to do in fixing this issue, the speed is vastly improved for now.