Honda IMA's are supposed to be used without assist/regen; using assist will drain down the battery pretty quickly; the IMA system will go into forced charging mode - forced charging increases the drag on the engine for the same given speed.
There was a pretty detailed guide about using the Honda IMA - Adapting Basic Hypermiling Techniques To HCHII -over at cleanmpg. But for some reason, quite a few links to cleanmpg are broken atm.
What it basically said was this: IMA should be thought of as an electric turbo; it should be avoided as much as possible.
@saadhasan99 most cars get poor fuel economy with short trips. I can bet that at least half of your journey is spent warming up the ICE. The IMA system doesn't work properly unless the coolant temperature is above a certain value. Letting the car idle for 10 minutes before taking off is no good either; you will waste even more fuel that way. There are general hypermiling and IMA specific techniques to get around this; for starters try to find an engine block heater. It will give you a huge improvement.
I will post later with advanced hypermiling techniques; as I said, most links to cleanmpg are broken atm.
