Sure, I realize that. (Although "subsequent calls are not independent" means it's not actually refusing to respond "at random".) I'm just pointing out in a facetious, emoticon-marked manner that "it behaves randomly" is kind of an odd insult to level against a source of randomness.
I think the point is that it should behave predictably (but of course give you random data). Behavior is a "larger" concept than just what kind of data you get from a thing.
You can quite predictably drain dev/random and make it not respond randomly. in the 257-valued joke's terms, you can force it to always emit the blocking behavior.
