@justintanner I asked the same question about a worn out card but searches on Ebay, Ebid and Delcampe suggested otherwise with ‘worn cards’ exceeding cards with a clear MACGREGOR…
Just done an Ebay ‘loch tay macgregor’ search which returned 10 examples of the card all showing the same or similar wear and 1 example showing a clear MACGREGOR where the first G of MACGREGOR is much better defined and the spacing of the second G and O appears different to the TuckDB card example. The back of the card has also changed as it now has COPYRIGHT LONDON in small vertical print in the bottom left corner.
Don’t know about Tuck printing processes but would the guilt lettering be applied to the white background box so any wear would expose white rather than more guilt?
I think on balance that at some stage Tuck changed the two letter Gs in MACGREGOR at a card reprint when the back was changed to make MACGREGOR clear.