This fellow does it ... clutchless shifting

https://www.rx8club.com/showthread.p...utchless+shift

But then again, he says he's a seasoned veteran when it comes to MT. I personally would rather replace the clutch vs transmission.

Definitely, it's the synros trying to engage the gear as was said before. Syncros are a cone shaped ring that make contact with the adjacent gear to help match the gear speed before the teeth actually engage. It seems like a LOT of unnecessary wear on the syncros, so in short - dont do it!

Many (if not most) cars don't have a syncro for the reverse gear - this is why you hear a grind when you put them into reverse. I have formed a habit of always engaging a forward gear (with the clutch IN) before putting the car into reverse because of this.

Shifting gears (either up or down) is very doable, and if done properly (i.e. without grinding gears) does not harm anything. I have done this in every stick shift I've ever owned to keep my engine rpm matching skills up, plus you'll be a much smoother driver. I heel-and-toe just about every down shift. If you match revs when shifting (even with the clutch), you're syncros will theoretically never wear out.