[pcwalton]

    let f = function() { ... g(); ... }
    let g = function() { ... f(); ... }
    f();

Works despite the temporal dead zone and depends on hoisting. This exact example is why hoisting was kept for let.

[mercer]

Interesting. This kind of stuff makes me want to dive into the details of these kinds of choices, as I regularly wonder why languages designed are a certain way.