[Crisp]

When I owned my 6speed GTO, I always rev matched unless I was using the clutch as a break to combine engine braking with regular braking for more barking power.
I would do this once in a blue moon (use of such heavy engine/clutch braking).

Otherwise, I don't see how it's possible to go from 6th gear at 2k RPM to 5th gear 2.5k RPM without there being a jerk....unless you are riding the clutch out slowly which would obviously take longer.

However, I also rev matched a lot because when I downshifted it was for more power, so my downshifts would be from 5th to 3rd for example, and this would be at least a 1k RPM difference which would be very jerky unless I rev matched.