With an automatic it is hurtful to transmission to switch from neutral to drive when car is moving. However neutral is really benifical for pulse and glides and general coasting. In drive the car just engine brakes. Recently I noticed this engine braking goes away once the injectors come on at low rpm around 1100rpm.
So I opened my ECU ROM in Romraider (a subaru open source flashing system) and found overrun fueling tables. I just raised overrun fuel injection rpm from 1100 to 4500 rpm and now my car doesn't enter fuel cutoff at all.
Its really helpful for gliding and coasting as the car literary goes the extra distance now. I don't need to drop the tranny into neutral and induce wear and tear. Of course the consumption is not as low as in neutral but It's close and more practical.
If you coast a lot I find fuel injector cutoff to be useless and unhelpful. My mileage improved now since I pulse and glide a lot but I'm guessing for an average Joe consumption might actually go up.
next up is lean burn xD