What you do
after accelerating is far more important, in the big picture, than
how you accelerate. EG. if you're regularly forced to brake after high load acceleration, your fuel economy will end up in the toilet compared to feather-footing up to a stop.
vielecustoms: also be careful about drawing conclusions about what works and what doesn't based on driving conditions / routes that aren't identical. EG:
-- as the weather gets colder your mileage is dropping.
-- If the new route is
significantly short enough, you'll get worse mileage simply because the car spends proportionately more distance coming up to full operating temperature (not just the engine - the whole drivetrain, including transmission, tires, bearings...)
-- You might have had a short fill on the bad tank (unless you're filling to the brim every time)
-- Sounds like you're still dialling in the
ScanGauge accuracy. If you're
"driving to a target MPG" when it's optimistic, that'll obviously lower your actual numbers.
You're in the Adirondacks, I see. You should consider going out to one of the AMEC economy events in the spring. Even if you didn't compete, I bet there are people who would be happy to talk to you / demo / give you a clinic on technique if you're interested.