And select a low gear, where have you seen engine braking advised?
They fitted retarders on vehicles which use the engine as a compressor to slow the vehicle down, or an electric retarder which mainly used on coaches was a device on the propshaft, that induced an electric force which slowed the propshaft down, thus slowing the vehicle down, the selection of a lower gear especially when going down a steep hill, was done after the vehicle had been slowed down to a suitable speed by using the footbrake,, not using the footbrake and changing gear at the same time, the idea was to avoid heavy braking going down the hill and avoid brake fade. If the driver was unable to engage the correct gear through trying to change down at too high a speed for instance (usually on a crash box) the the vehicle would technically be out of control and liable to brake fade, one of the commonest places this happened in the old days was at Brighouse.
The use of a lower gear is normally engaged after braking, for instance on the approach to a sharp bend, the vehicle should be slowed down using the footbrake, and a suitable gear should be chosen to navigate the bend, and just enough acceleration should be used to take you around the bend at the same speed you slowed down to, to negotiate the bend, if you have to brake whilst going around the bend, it would show you are going too fast, and of course you would be steering with only one hand on the wheel, and the braking would make the vehicle unstable..
Many think that the introduction of automatic gearboxes in HGV's was done to save fuel, they were introduced to save wear and tear on the vehicle, renewing brakes on a HGV can be done in a day, a gearbox can take a week,, probably longer if it is repaired rather than replaced.
VSG is an acronym used,
V= view the obstruction /hazard ahead.
S=get the speed down to meet. whatever is ahead.
G=select the correct gear to negotiate the hazard/ahead
Always avoid secondary braking..
Ref toe/heeling not what you should be doing whilst driving a HGV, and not possible in a lot of vehicles due to the offset in height of the pedals. possible in a car, but what benefit?
(only my opinion on these matters, after 50+years in the transport industry, Both as Driver, Trainer, Assessor etc)