Finally! Some validation, if not vindication... PPro should be able to play back GoPro files in real time, and it currently doesn't. The problem is with the software, (usually) not users' hardware.
I wonder what is it about the GoPro MPEG4's that makes it such a PITA for Adobe to resolve, but it's beyond my resources to find out. What's needed at this point is user pressure to escalate the issue and demonstrate to Adobe that it's an issue worth spending their time on. First, everyone is invited to file feature requests...