Compression test on a 360, result OK or not?

AJ/FormS said
A Sticking intake valve will allow the piston to push charge back into the intake causing a momentary increase in pressure.

From the action of the needle,in the subsequently posted video, I agree with Mattax, who said

Mattax said
Looking at it, I don't think its a valve issue, the way it wanders up and down.

Have you got headers on that beast?
And if yes; are they properly sealed at the head, and at the collector, and in the merges?