So many assumptions, but none of these apply to my situation.
I drive a car from 1989 with a transaxle mounted gearbox, so my gearshifter is not above the gearbox, making it very indirect and thus doubleclutching is improving my gearshifting speed plus making it more smooth.
I would never force it like a madman into the next or previous gear. It's never good for any car to as you say switch gears very fast, if this means slamming the shifter from gear to gear. But this can only be understood if you have a feeling for technical installations.
It does hurt something, just because it's new doesn't mean it cannot wear. Maybe you don't notice it wearing but I can guarantee you everything that is done mechanically wears in one way or another.
In new cars, the synchromeshes do wear more quickly if you treat them like they're worth nothing by not being gentle. So I wouldn't say it's pointless.
If you have no technical feeling and sometimes making your gearbox whine when you slam your gearshifter in reverse like a granny, that's too bad because it's always better to relax and be smooth. I could make an assumption here, if people around you have this attitude towards their equipment, this doesn't mean it's the correct attitude.
As said on wikipedia nowadays gearboxes are automatically synchronizing between gears, but in (very) old cars and in cars with a worn out clutch you have to match the revs of the previous gear.
If you have mastered this technique you can switch gears in any car without using the clutch, but I wouldn't recommend doing this unless it's in emergency situations involving a car with a worn out clutch.
I just feel like it would add to the realism of the game because in real life when you shift gears, you always go into neutral between gears with any H pattern gearbox, unless you are driving a semi automatic gearbox.
I try to do it always when I'm downshifting because it makes the downshift much smoother.
If you're not playing with a controller that has an H pattern gearbox, whenever you shift gears, it immidiatly selects the next or previous gear.
My suggestion would be for the game to have a setting where it will always go to neutral in between gears.
I don't want to change the game for everyone, but I have been wondering why this doesn't exist as an option in the game. If it does exist, please ignore my ignorance and point me to the location in the menu of this setting.
In my opinion this would be fun to mess around with, especially for new demo players who have yet to explore sim racing. Because if this setting would exist, then it would be possible to practice double clutching to some degree without having an H pattern controller.
Example of driving with this setting: You're driving in 4th gear, you hold the clutch, hit downshift and release the clutch, now you're in neutral, again you hold the clutch and hit the throttle, hit downshift again and you're in 3rd gear where you release the clutch.
I think it would be fun to do this when using a gamepad such as the xbox controller, or even playing with keyboard and mouse, perhaps in situations where you aren't home and feel like goofing around.
I know the realism isn't up to par with a proper sim racing setup which has the 3 pedals and an H pattern gearbox but it would be a fun feature even if you're using solely buttons to control the car.
So I'm not trying to say it's to have a good way to play the game compared to the better controllers many players here are using, but a lot of (young) people don't own a serious setup (yet) and this would perhaps spark their interest in live for speed racing more over other racing games, and having more features in LFS compared to any other "racing sims" even though they don't get close to the realism offered in LFS would be a plus.