Intensity curves
 

So I just got some great help from Blinn and Roach on my fog light, but I did something dumb. I deleted all but 3 of the keys in the graph editor. Now I find I want to add some keys back in, but the Add Inbetween function doesn't do anything here. I'm guessing it's because this curve isn't based on time, but rather distance.

I know I could just ditch my curve, and remake it, but it brings up a question... Is it possible to add keys to an intensity curve?

I just saw the GIANT, OBVIOUS "Add Key" button on the top left.

They don't work either.