I suspect that feathering the accelerator will result in lower mpg than accelerating "normally" or slightly faster than normal to a few miles per hour faster than you want to go, then feathering the gas to keep your speed from going too low.

An obvious exception would be creeping between red lights on EV power. Then feathering the gas to avoid the ICE starting between red lights makes perfect sense.

I find I can "take off" from a stop without the ICE if I gently get rolling, then add more power until I'm accelerating at a slow but steady pace. However if I'm going to go much faster than 20mph or so, I think it makes more sense to use the ICE to get up to speed, then back off and use EV mode if I've only a few blocks before stopping again.

I'm 570 miles into my 3rd tank, showing 43.5 on the tank average. If I could avoid more short trips and AC usage, I know I could get the mpg up higher. The best I've seen was 46mpg for 210 miles on the tank average.