Thanks! - and I'm with you on the 3K for boil. I did try 2.5K for a little bit and while it maintained a boil it just seemed more vigorous at 3K.... However, the manual says the 2,000 element alone would keep a rolling boil! Have you tried this?
I may try 2.5K for the whole boil next time - just to see.
My experience with my 35 matches yours: the big element boils, but both together really BOIL. For me, it only costs a little more, yet I get better than 4 quarts an hour boiloff. I'm using both every time.