Contrast Stretch effect broken?

The "Contrast Stretch" image effect doesn't seem to be usable, due to the "adaptation speed" being ignored.

No matter how low or high I set this, the contrast stretch seems to be immediate instead of gradual/lerped. For example, standing inside a dark building and looking around causes the contrast levels to constantly flicker up and down as the camera takes in the lighter parts of the wall. Moving from a dark building into a brightly lit outdoor scene also instantly switches contrast, and moving the camera around while pointed at the sky causes the contrast to immediately change every time I look at a cloud.

 

Hmm, so the Adaptation Speed isn't actually ignored, it's just too fast even at the very lowest setting, with the overall shader just being too sensitive to small light areas in an otherwise dark room. It provides a good contrast range, but does not emulate the "walking out of a dark room into sunlight" effect very well at all, IMO. RElam's shader achieves this very nicely, with the fade being applied slowly.

Standing inside an almost completely dark room and walking out into the sun with Unity's built-in effect does almost nothing, while this third-party shader gives you nice blown-out whites on the clouds, etc, which fade back to "normal" after a second or two.