The transmission’s input shaft will spin-down from momentum, but it’s ***output ***shaft will always spin at the speed that the back (or drive) wheels are spinning. If you’re stopped, so is the output shaft. But if you’re moving, even coasting with the clutch pressed down (disengaged), the output shaft inside the tranny still turns in unison with the tires. This gets at the OP’s question. While coasting, again even while holding the clutch down, if you then push the stick into say 4th gear you have just caused the input shaft and the clutch disc to spin up to their speed. This is fine for 4th or 3rd but if you try and push it into 2nd while coasting at high speed it will resist going into gear because, again regardless of the clutch pedal still being down, you’re now trying to make the clutch disc spin at the speed required to drive at highway speeds in 2nd gear. At anything above zero, even just a few mph, it will take effort to get the stick into first, so going into second, then first is easier because you’re speeding up the input shaft & clutch disc more gradually.
My cousin in his ill-spent youth once forced a Ford dealership’s parts pick-up truck into 1st gear while coasting above 50mph. Even without releasing the clutch pedal the clutch disc promptly exploded as it was probably traveling at over 10,000 RPMs!
When downshifting the engine rpm needs to go up to match the speed of the gear. Going from high gear to low gear means a greater increase in RPM and 1st is usually the gear with the greatest difference in numerical value compared to other gears. Shifting to 2nd makes the transition smoother. Or put another way it gives you something to do while slowing the vehicle down.
Except for starting off in 1st gear you really don’t need the clutch. Synchronizers make it possible to preload the gear so that it matches the speed of the engine. that works with or without the clutch but if you’re kind to the transmission you can shift without the clutch. You need only properly match the speed and gently engage it.
There’s a good explanation of double clutching at:
Also, doing the timing and throttling part of double clutching lets you drive when the clutch is broken and engaged (for example if linkage is broken). You don’t actually need the clutch, if you get the speeds matched up closely enough. The exception is if you need the engine to get the car moving from a standstill (if there’s no downhill slope), and as far as I know the only approach here is to stop the engine, and start out by using the starter motor to restart it in gear. This also has the advantage of letting you play “bucking bronco” without going to one of those bars with a mechanical bull.
I once broke the clutch thow out bearing on my 1959 Ford pickup. I was able to drive it home from work that way.
The next day my wife took our only running rig to go grocery shopping. She did not get back in time for me to take it to work. I fired up the Old Ford in first/granny gear and drove to work that way. If I could slow down enough to get it into 2nd about 1/3 of a block before a red light, I could creep along at idle until the light changed. I drove the 70 miles to work without killing the engine. Coming home the next day I did it again.
My wife had gotten her dream job, it started the day after this happend. She got the car and I drove the pickup with no clutch for several weeks. This went on until I got a weekend off and had the time to repair the clutch on the Old Ford. The snow was too deep for the motorcycles. I could have just bought a junker to get me by, but I saw no reason to.
If one does this for an extended period of time, (many months or years), the starter ring gear on the flywheel will wear the gears off. It will need to be replaced, along with the starter’s gear, when the clutch repair is done. Do not AMHIK!! :)
“They” who? my brother’s old Alfa, or your Jetta? Bro does’t have the Alfa anymore, but I’m pretty sure there was no syncro on reverse, i.e. you wanted to touch second gear (or pause for a couple of seconds after clutch-in) before putting it into reverse.
My 2013 G37 has syncros on every gear, including reverse.
