Common Fallacies about Gear Changing
The method prescribed by the British police is ‘Gears to go, brakes to slow.’ This system forbids the ‘overlapping’ of braking and down-changing phases as they don’t want you doing both at the same time.
Before the invention of synchromesh gearboxes, finding a gear was like stirring tar. To get the cogs to disengage you had to pump the clutch pedal, then blip the throttle to match the engine speed and finally operate the clutch again as you selected the gear. Your feet couldn’t be everywhere at once, so this necessitated a separation between braking and down-shifting. In short, there might have been a good reason for splitting the phases in the 1930s, digging out the next ratio with a gear stick that resembled a crowbar.
The separation of braking and down-changing doubles the distance required to slow down, or, as the police manual neatly explains: ‘The problem is that if you brake some distance before the turn to avoid an overlap, you can confuse other drivers… (who) may be tempted to overtake.’
Engine braking gives you more stability in a corner and when you descend a steep hill.