The best video I've seen is the outdoor Arizona springtime shot with backlighting, and multi-strobes, and keeping a long shoot very consistent in terms of the percentage of flash-to-ambient...this is the kind of thing I have to compute manually, laboriously, because my meter reads flash at only two speeds: 1/60 second, and 1/250 second, and I have to meter ambient separately from flash illumination. A higher-end meter would make this outdated method unneccessary.
The other issue is for studio shooting when you want to be able to meter the lighting on the subject's face in incident light mode, and them immediately meter the reflected light value of light hitting the background and coming back to the subject, without the need to stop, and remove the dome, and then slip in the reflected light metering attachment...this is part of that background density/color measuring that commercial and pro shooters want to be able to measure, and test, in order to work fast, and repeatably, over hours, or days, or over different sessions.
The 758 dates to a time almost 10 years ago, when they had software that would allow the user to test the RAW file capability of their specific camera, and to then input profile data that would show the REAL, actual, recoverable highlight exposure of the RAW, and not the in-camera JPEG file the histogram reads off of...this was something that only a few people were really in need of, I think. But now, many cameras are much better in terms of total DR that the sensor can handle, yet still.
The incident metering for subject/reflected metering for background/comparing those two is a fundamental principle used whenever a gray backdrop, or a cream backdrop, is measured to get that just-perfect white background value, or to establish the exact gel-saturation level when one needs to "fake" a backdrop color using a dark or gray seamless and a colored gel....INCIDENT-only metering simply cannot establish either of those values: you need a reflected light value, so that's partly what the higher-end meters offer: quick incident and quick refleced light readings, and precise, real-time measuring and readout of ambient-to-flash percentages (not ratios, but simpler percentages).