The same way you need to change the habit not to floor accelerator when driving Ferrari unless you're on empty highway, you may want to change the habits when it comes to fuel efficiency of your TCH, but you really don't have to. Every car is different and to fully explore limits of each you need to learn a little besides passing the driving test to get the license. Hybrids are new and have some quirks that are different from what you may have experienced in the past. Either way, if you learn to drive more efficiently or not, TCH will have better MPG than similar ICE only car. I doubt Toyota will allow reprogramming of ECU, not with 100k/150k mile warranty on batteries we get. As a matter of fact forget about hacking ECU, I would be extremely happy if we at least had few mechanics around capable of fixing the thing if it breaks. I believe TCH has some limited capability to learn drivers habbits and act accordingly anyway.