to my eye, all the pics are blurred due to some form of camera shake/not short enough shutter speds. All of the birds are blurred too.
I agree, the birds look blurred too: look at the spots on IMG_8685.JPG. It does not appear to be a processing error to me, it looks like camera movement. When I first acquired a 100-400 I had a few shots similar to this on my 60D, and it turned out I needed to use a faster shutter.
"Inherent technical error of the entire 70D fleet" should be last on the list of possible causes. I'd troubleshoot like this:
* Rule out user error (full-camera shake) by testing on tripod with remote release or timer
* Rule out faulty mirror/shutter mechanism by using live view with zoom (and tripod with remote)
* If you still see the problem, then call Canon for service
For your test target, I would choose an inanimate (non-moving) object, and don't use flash.