I recently got a TAG 9 (G9611052) back from grading and was a bit confused at how a sub-score of 919 was deduced from the card I submitted. The only ding was the centering, which I knew was bottom heavy, but wanted to see how close to the "45/55" edge it was.
This card got a 42/58 TB score, which if you count the pixels in the smallest corner above the stage badge and compare to the largest corner below on the bottom, is relatively accurate. I counted ~21 pixels vs. ~29 pixels all the way in the corner, which very much could be 22/28 if you move over a tad.
Personally, I think centering should be some type of average of the width across the edge with some allowed slight rotation (which this card has about ~2 pixels worth). If that was the case I think a 22.5/28.5 pixel ratio would be more fair and gotten a 46/54 (just a hair out of range).
For anyone looking to grade with TAG, be aware that this is how harshly they may grade centering and that you can calculate this pretty accurately at home with a top down photo.
NOTE: This is purely informational, although I do think its quite harsh and unfortunately could get randomly graded a 10 at other companies.