Helge : Of course there are tests. I do them every single time I try a new film or encounter an unfamiliar lighting situation. I take my MacBeath Color Checker chart and run a bracket test with roll film, and see how much deviation from 18% gray certain color patches will still saturate at, or how much, etc. It is vital to have one correct box speed exposure in that series, and ideally, at correct color temperature. And a test in bright open sunlight is different in a test in soft light. You might need both. In other words, tailor these tests to your own circumstances, not web hearsay. "Go to the horse's mouth."
Any generic "spec sheet" is likely to be questionable. Everything is dependent upon how you want to reproduce your image. For example, much of the range you might be visually able to perceive in a color slide atop a light box or using a traditional slide projector might be difficult or impossible to reproduce in a color print. The limitations of offset reproduction in a book or magazine are even more stringent. And individuals have different printing abilities in the darkroom. Some of us have advanced skills and equipment, like for contrast masking; others do not. So there is no one single answer. You have to tailor exposures to your own specific needs and esthetic proclivities.
Actual printing tests of select patches follow. Then as things get more serious, I make a sheet film master neg or chrome of whatever film I standardize on, with a perfectly exposed and color temp balanced shot of the MacBeth Chart under representative conditions. I have em clear up to 8x10 film size. Those it turn greatly speed up color balancing of any new color printing paper batches or new types. I won't go into the complications of scanning and digital workflow; that should be addressed elsewhere.
Alan - "brightest" and "darkest" are relative terms if you expect to retrieve usable color itself. But the bracket tests I just briefly described will get you on the right track. I've been an outdoor photographer for about 60 years, and have worked with all kinds of chrome films as well as color neg, and have never ever found the need to use a neutral grad filter. I'm not condemning them, but have noticed just how easily they get abused to create fishy or phony looking images.