slajeune,

I was able to do some tests over 10 miles today regarding how many bars of assist to use in ev-mode p&g on the 06 hch

it depends on the amount of battery charge you have:

7-8 bars of battery charge: during glide mode, use anywhere between 0-5 bars of assist. Don't worry about the battery drain: you have plenty of battery charge to use.

5-6 bars of charge: during glide mode, use between 1-3 bars of assist. You don't want to keep draining the battery too much anymore. 5 bars of charge is the optimum level you settle at - reaching a balance between assist and regen during pulse and glide intervals so that your battery remains steady at 5 bars. This is a good equilibrium point, I found, where forced regen is at most 1 bar that hardly affects your FE.

0-4 bars of charge: don't enter glide mode until you get at least 5 bars of charge back again. During this state, there will be 3 or more bars of forced regen that impacts your FE significantly. You're better off holding your speed or doing some slight driving with the load. (let speed decrease 5-10 miles per hour uphill, let speed increase 5-10 miles per hour downhill by holding your throttle steady)

I also found that the HCH is excellent in the city - maintained 60.0 mpg using pulse from stoplights and ev-mode gliding/braking in heavy traffic.