I ramped up the PSI from 40 to 50... 25% increase.
Yes I did notice an improvement! But I am well exceeding the safe range to run these, toss in the kid trailer and I really would hate to blow a tire pulling them. So I figured since I did notice a a nice decrease in rolling resistance I need to change out to a higher PSI tire so I can take advantage of it without living on the edge.
From the recommendation of another forum member I picked up Kenda Kwest High Pressure 26x1.5 Black. They have a higher pressure rating of 100 PSI and they are slightly more narrow.
Ordered em form AE Bike and they are on the way!