For hybrids it is generally referred to as a pulse and glide. I'm only really familiar with the 2nd gen Prius, but a hybrid can make hypermiling easy. It comes with nanny systems that limit the amount in order to protect the drive train and battery, though. With the Prius, the goal was to pulse, and then feather the accelerator. Foot off the pedal had the regen braking come on slightly to simulate transmission drag. By feathering it just a little, that would turn off without the engine or motor coming on. It is the same outcome as shifting to neutral without an idling ICE.
A hybrid could shut down coasting down hill and other times, but other factors come into play as to whether it does or not; such as engine temps and the battery's state of charge. Forced auto shut off is used by original Insight owners for the times the car's computer decides to keep the engine running. With every manufacturer's system being different, blanket statements are difficult to make.
Supposedly, Ford's current system is different enough that the techniques used on the first one aren't nearly as effective. Then Hyundai's system with pulse and glide automatically while cruising of the highway. The 3rd gen Prius has better rating EPA rating, and it is easier for the typical driver to attain it than the 2nd gen, but the 2nd gen has a higher MPG potential.
If you are gauging potential has a ratio of their rating, then a hybrid's potential isn't as great as an ICE car for most. They are already using some of the hypermiling tricks to get their rating. In raw consumption, few ICE cars will match a hybrid though. Double of the 2.2L S10's combine rating equals the 2nd gen Prius' straight rating. Getting that rating on the Prius doesn't require anything from the driver beyond avoiding short trips and not racing around everywhere.
Getting double of the S10 rating involves advanced hypermiling techniques. Using what that level, 4 men got over a 100mpg in a gen2 Prius over a tank. Some of them admitted to trying to waste fuel towards the end, because they were getting tired of driving. Wayne Gerdes, coiner of the hypermiling term and owner of Cleanmpg.com, has a record of over 180mpg in an original Insight for competition level hypermiling.
If you are looking at modding for economy, Ecomodders.com is a good start point.
__________________
|