Simpler, but not effective. In almost every country in the world, copyright vests in the author automatically, even if the author doesn't use the old "All Rights Reserved" magic words.

Practically speaking, not including anything about copyright is just going to make your users (or their lawyers) ask questions before they ship, or before they're acquired, or....

If you really want to put it into the world for anyone to use without restriction, put it in the public domain (e.g., http://creativecommons.org/choose/zero/). But public domaining doesn't happen by accident — just failing to mention copyright doesn't cut it.

I agree that you're probably better off not mentioning license terms at all. That may keep people from using your thing as intended, but it will also keep people from maliciously misusing it and then dragging you into an unwinnable game as a consequence.

As such, I'd much rather say, "You can do whatever you want with this, provided that you don't use it to hurt me."

And as long as you're there already, you have lost the simplicity of a single sentence clause, and might as well just use the MIT license.