Daniel_

I have driven a huge range of manual cars for 19 years, and have NEVER had to double clutch.

Very old cars (pre 1960s) have gearboxes that require you to get the speed of the gearbox to match the speed of the wheels in the gear that you are selecting - to this end one would drop into neutral, use the engine to run the gearbox to the desired speed, depress the clutch and engage the gear you desire.

Synchromesh gears are specially cut so that if you depress the clutch, move the gearstick to the new gear (with the clutch still down) in one smooth movement, the gears engage regardless of the speed that the inside of the box is running.

Bringing the clutch up slowly whilst adjusting the engine revs carefully will prevent burning the clutch or stalling the engine.

Back to the OP - if you step down one gear at a time you will put less stress on the drive chain.

On a safety note - it can be fatal to leave the car in neutral at speed - you have no option to accellerate out of danger if something bad happens in front of you - for the same reason it can be dangerous to leave the box in 5th and simply depress the clutch as you decellerate using the brakes.

For safety it is best to ensure that the gear lever is engaged for the speed you are travelling at, even if you don't actually re-engage the clutch.

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Overhead, the Albatross hangs motionless upon the air,
And deep beneath the rolling waves,
In labyrinths of Coral Caves,
The Echo of a distant time
Comes willowing across the sand;
And everthing is Green and Submarine
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