This is a thought experiment, obviously this is not real datomic!

Why do this? I think it would cancel out data transformation boilerplate currently needed to do something like this.

```clojure
(defn user-uuid-to-user [user-uuid]
  (d/q [:in $ ?user-uuid
        :find ?user .                          ; no pull here, bind it later
        :where [?user :user/uuid ?user-uuid]]
       *$* user-uuid))

(d/pull $ [:domain/ident
           {:hyperfiddle/owners                ; :many :uuid
            [{user-uuid-to-user                ; a fn that navs deeper, takes uuid as input
              [:user/name                      ; now we can pull deeper as if the relation was a ref
               :user/email]}]}]
        [:domain/ident "tank"])
```

Someone who understands rules can probably make this simpler.