Can I just say one thing, Brakes are for stopping, Gears are for going! You should be using the brakes to slow and selecting a gear that is suitable for the speed you are doing. Engine braking is alright in small doses, in the right situation, such as steep hills, but shouldnt be relied on for other things.
That was also said in a recent article on riding in a couple of "respectable" bike magazine by a very experienced instructor, before anyone wants to kick off
Driving anything that has passengers without seatbelts, such as an ambulance, bus or even a HGV with livestock on is a different skill altogether.