This person replaced the flywheel, clutch, slave cylinder, and CKP (crankshaft position sensor), and claims the issue was resolved for them:
Misfire Code p0300
Given that my car is almost certainly on its original clutch and flywheel, and the previous owner and I experienced the problem when the car was stock (they replaced all 6 ignition coils, too), this made me curious.
Zooming out for a moment, all of this seems generally limited to 2009-2012 Zs, and it makes me wonder if Nissan built them with a substandard part that was later improved through QC. It could also be something that happened occasionally during shipping or assembly before Nissan implemented process improvements or better packaging.