For best BSFC, it's high load and low rpm, which we can not do with the atx, so I just try to limit rpm based on the idea that the torque converter may be more effcient and have less slip with less rpm...it seems to work with my car. Keep in mind that you will be accelerating at a slower pace than 99% of everyone else. When I am going stop light to stop light, I will let it shift up to second gear then attempt to coast up to the next light, assuming it's red, this can drive the folks behind me crazy
but we usually get to the light right when it turns and it causes no delays. The idea is to only build enough speed to get you to the next red light. If it's green, then you just want to go as slow as is reasonable.
Thanks for the nice comments, it has taken 2.5 years to get here, so don't think you will get that 40 number right away or without some failures along the way.
I commute into Philly everyday, so I get to fight plenty of traffic. I've been around Dallas as well, so you have a similar problem. Work on your route, there is often a lot of potential there that most folks ignore.