Good Evening!
The Digital Dog kindly gave me 900 near-grey patches optimization file for i1Profiler.
Having used it for my paper profiles and been very satisfied. And today I tried it when I calibrated my screen on the monthly basis.
Finally the black and white gradient shows a true black to white with no color cast.
Being unaware you could use the spot color files in display calibration mode before, this was a happy finding, I thought I'd just share it with you as well.
Kind Regards!