So if $hashref contained a hash, then you could access the whole hash with %$hashref (the hash % in the scalar reference $hashref).

Aside from your advice to leave in all de-referencing arrows, which can be good or bad depending on the context—for example, it can make it clearer to a new user what's going on, but it also completely destroys the often-intended resemblance to a multi-dimensional array (or hash)—I think most of your post is a good description; but you probably didn't say what you meant above. Of course the point is that $hashref doesn't contain a hash (or else it would be %hash or something), but rather that it contains (or perhaps just is) a reference to a hash.