I think I've found the trick to Pulse + Glide (engine on) my Volvo 
I had been fooled by reports of careful acceleration at less than double the regular FC for the average speed, but that technique just doesn't seem to work in my car.
Acceleration in my car means the FC shoots up sharply, and doing it gently means the pulse is far longer than the glide while FC is still rather high during the pulse.
So I've resorted to brisk acceleration in a fairly low gear.
Surely it uses a lot of fuel while accelerating, but the pulse is very short compared to the long glide.
With a warm engine, I've seen the average mpg increase while P+Ging through the city.
Before I started using this trick, FE invariably became worse during the city-part of my commute.
At the moment I'm only using this modified P+G technique on selected parts of my commute, but traffic permitting, I plan to start using it on the longer stretches of road as well.