Just went out and adjusted it to 1mm slack as you advised. The cable felt free but I put some oil in there that will work its way down, too.

It took 3mm of cable-jacket movement in the bracket to get that, so the cable was tight by 3mm (under tension all of the time by 2mm), and probably commanding higher shift line pressures to upshift, explaining the harsh/late shift.

There was also a rubber boot over the cable (to prevent dirt/liquid ingress) that because of a crimp-on ferrule, prevented the cable from fully retracting into the sheath. I popped it loose to make the cable free-enough to see how it shifts.

We'll use the car tonight and will see the change, and go from there.

Thaks-
Bob