Here are graphs of profiles obtained from 1831 and 1218 patch targets, printed at the same time on adjacent sections of the same canvas, and read back to back. Old style i1ProPhoto puck, latest i1Profiler software.
The wireframe is the profile I got with a 1831 patches, the solid hull is the profile obtained from 1218 patches.
There are some really significant differences, particularly in those blue and violet colors that are so elusive on matte media. The 1831 patch profile does a lot nicer job on transparent blue skies, and you can see it on prints.
So, now I don't know what to think. I assume the 1831 patch profile is truer and better because it looks that way on prints. But the 1213 patch profile also yields very nice prints, but is clearly second best in the graded blue sky department. At any rate, I was surprised to see such a difference. Of course, I've only got two samples here. Maybe I need to knuckle down and try this a few more times. But even on this example I read each target twice, and there are essentially no discrepancies between reading sets on the same targets, because their graphs overlay perfectly.
Do you iSis jockeys see similar differences?
So maybe the moral is...you can benefit from lots of patches, and it may be very worth your while to use targets with with upwards to 2000 patches.