It's better to overrev when you're matching a shift than to underrev, too: example:

I'm once again in 6th gear at 60MPH at 3,000 (this is true in the RSX)
I want to shift down to 5th gear because I'm going up a hill and I want some added power

1. Clutch in, move shifter from 6 to 5
2. During the shift change tap the gas and I hit something like 5,000
3. I let the clutch out at say 4,800 in 5th gear
4. Correct 5th gear RPM at 50MPH happens to be 4,000
5. Engine automatically slows down to match transmission speed

That is less wear-and-tear on your syncros than this:

1. Clutch in, move from 6th to 5th
2. Rev to 3,500 during the shift change
3. Let clutch out at 3,300
4. Engine speed does not match transmission speed, syncros get engine up to 4,000 resulting in a whine noise/bog motion


I'm not saying that overreving to match RPMs is GREAT for your syncros, but for someone like me who doesn't always perfectly revmatch, overrevving is better.