Is there a mechanical, mph influencing, difference between Glide and Neutral for low speed (say 20 to 35 mph) operation? Of course there is a safety/legal issue so I'm not recommending Neutral as a substitute for using the accelerator to glide.
Battery charging doesn't happen in Neutral, but does when "gliding". This will effect fuel economy a bit. The switch to power train braking is instantaneous in glide but you have to use the gear "shift" when in Neutral. Which is one reason for the safety/legal issue.
I thought the whole point of glide is to not be charging or discharging. You look at the Car display and try to position the accelerator so there are no arrows pointing into or out of the battery. If you are charging then there is a drag on the car which defeats the point of "glide" and I believe that is called "coasting".
Nevertheless, you need to convert some momentum into charge or your system isn't going to stay charged. The higher the SOC in the battery, the more power the system will use from it. You can use N for some coasting, but not all the time. I'd say if you're not at or above 6 bars on the SOC, don't use N.
There are several things that happen in N and you need to understand them before using it very much. One of the biggest is that all Synergy control of the various systems is turned off. The engine will not restart, or if running will continue to run. All regenerative systems are turned off (braking is hydraulic only). There are probably more. There are some very specific instances where N is useful....a search should turn up the necessary information.
I've wondered this. My big question is other than comfort and concentration why wouldn't you just lightly hold thr ggas down hills. Seems like when I neutral glide my gallons per hour is still at idle level.
If your engine is running when you put it in N, it will use fuel to stay idling. When decelerating or perfectly gliding, the engine may still rotate, but no fuel is used. N is legally required in the US, but as implemented in the Prius, has very little to recommend it. The less you use it, the less it will bite you. (you can't charge the HV battery in N, you have no regenerative brakes in N, etc.)
I understand 'glide' to mean that the ICE is stationary, and is reported by the car by turning on the 'EV' light. In terms of efficiency, it takes 1 - 2 kW to turn the ICE. That is 10 times the energy losses from battery trip conversions in the ranges of driving we are interested in. Bottom line: Glide when you can, and do not worry about a little battery use in or out.