I read once a question on whether it's better to rapidly accelerate to your vehicle's most efficient speed / gear, or just creep up to it.

In my old wagon, once I hit 60kph (~40mph) it goes into 4th and drops to ~1250rpm. I tend to use moderate acceleration up to that speed then just chill.

I also recall the term 'pulse and glide' from hypermiling which might have some relation, but without the gliding bit.