[loganb]

Promises are about as clean as you can get in a purely async environment.

Yet, notice how no one shows off how easy it is to write a loop. Oh, and what happens when your code throws an exception? It's as though that path halted forever.

Also, what happens when you have a method defined as

result = foo(args);

that now needs to perform an async operation? Enjoy refactoring every call site.