The wordsmanship and joking about "real" immutability are in no way unfamiliar stuff to people in other languages, Ruby aside. In Java, it's the same deal, where maybe you can't change an object's fields, but it's fields' fields might be mutable. One layer deep, shallow freeze, shallow copy are actually pretty well understood concepts by "non-Haskellers", as well as the drawbacks and the need oftentimes for 100% deep guaranteed immutability--and the advantages and safety that brings. I think that the joke is that the label "immutability" in languages that don't support it from the ground up--unlike like Haskell--isn't really worthy of the name. But since we already dubbed them as immutable objects (even though they weren't really) you need some extra emphasis for true immutability...super immutable, seriously immutabile, really-really-immutabile, etc.