Ok, can you clarify this part from the link above:
"For most high altitude balloon flights, the Federal Aviation Administration does not need to be notified prior to the launch. However, as described above, if you are subject to the provisions of Subpart D, then you must contact the FAA."
If you don't need to notify them, it sounds a lot like you don't need to ask for permission? I.E. How can you have permission if you don't notify them?
Would really appreciate the clarification.