You are mixing things up:
Originally Posted by retro film
-) the intended viewing situation of an unfiltered transparency (exposed by illuminating a scene with standard light)
-) a laboratory made graph intended for comparison (where by added filtration the layers are exposed to yield a neutral grey).
Don't put too much emphasis to these data sheets. For instance, those spectral-dye-density curves are only recently added to those charts. And the interpretation of many graphs is beyond the command of the mean (including progessional) photographer. Furthermore the comparison between graphs of different manufacturers can become tricky.