[hyperpape]

I think you're substantially misreading. The author is saying that people describe loss aversion in ways that are not obviously distinct from DMU. He does NOT say that they're the same. What he says is that most definitions do not distinguish loss aversion and DMU.

You give an example where DMU doesn't explain the phenomenon, so we can see loss aversion. He might be happy to accept your example. But that doesn't mean that in general you don't have to point out that they're distinct, because your case is rather extreme.