It might outline the idea, but reality and the law doesn't quite work like that.
Nothing takes the place of a document spelling out your rights under whatever license the creator decides to grant you, hand signed by the copyright holder. That document is proof of permission. Anything else, no matter how fluffy and feel good it is, is not a suitable legally binding substitute.*
Well, yes and no.
As the owner, you're able to do whatever you want with it. If you declare your license to be what she's described, then that's it. e.g. If you release something into the public domain, well, there it is. Done.
The reality is that this is a bit of contract law that has never been tested in any court. So, how the courts would deem to screw people over is as of yet unknown.
Here's a license that I'll just pull out of my ass:
THE RENEGADE ETERNAL ALDEBARAN LICENSE (A.K.A. The REAL license)
You are hereby granted an unlimited, perpetual and non-revocable right to do whatever you darn well feel like with the materials pursuant to the following conditions:
a) You may not seek legal recourse for any of your use or non-use of the materials.
b) You agree that no court may make any ruling on your use or non-use of the materials.
c) In the event of any loophole in the above conditions, you agree to the exclusive jurisdiction of the courts of the Aldebaran system in the Taurus constellation.
It's a simple agreement that falls under contract law, but isn't enforceable by any of our corrupt courts. (Yeah, there are holes in it... it should be a viral license, but whatever - close enough. The point is that it hasn't been tested in court.)