ss - I don't have the answer you're after, but while you're waiting for someone who does can I ask you this? Does your eye "shake" make it difficult to focus on detail? I imagine it would, and I ask because your post has reminded me of something that used to happen to my sight in the year before I retired from flying.
If I needed to see the exact reading on a small instrument, and especially if it was urgent, I couldn't "fix" on it somehow. My point of focus seemed to skitter all around the needle point and I couldn't read the scale.
It didn't happen often, so I didn't follow it up, but I'd be interested if anyone has an explanation.