From your samples I doubt that there is anything to worry about unless there are some loose sensors out there. Could that happen? Who the heck knows.
Super teles are always a crap shoot. I get MUCH better results on calm days.
I also think there might be a touch of folks looking to create controversy one tough thing about drawing conclusions from a test is to see how repeatable that test is and what happens when some parameters are varied.
Perhaps the camera appreciates your old tripod. Experienced hands Eh?