You are not placing IWT in a macro.
You are sending a keybind to the wow game.

A Keymap =/ A Macro.

Looking at the Blizzard API, where they specifically allow addons to register one event on key down, and a different event on key up, tends to suggest this is now ok. At one point, this API did not exist, and I would have said it was not ok at that point in time.

Looking at the API and what it allows, the definition should read: one action per key action. Action 1 is done on they key action (key down) and action 2 is done on the key action (key up). It is two actions, on two key actions.

Blizzard is free to remove this function from the game, but it is currently an allowed function for anyone who can code an addon, or for anyone who can install and use an addon coded this way.

Lax is quick to include any functionality which Blizzard gives us, but IS Boxer sticks to what Blizzard allows; you cannot insert timed delays, perform loops etc.

As always, if you don't want to include key down and key up actions, you don't have to. Just spam twice as quickly, or go with separate keybinds entirely.