Jackson--I agree with you in general about the 1991 set having more variants than any other Topps set. And to your point there are few master 1991 sets I would say there may be none. But that could depend on one's definition of a master set. As far as I know there is no accepted hobby definition of a master set. What is yours ? Would your definition be different for pre and post 1980 sets ? What would be your definition of a master set for any Topps Heritage set ? What would be your definition of a master 1991 Topps set ? Do you have a generic definition that would apply to all sets ?
I do have my own criteria which I apply to all my sets but it breaks down somewhat on the more modern sets. I have a Topps run from 1948 to 2015. I consider my set master if I have all variations listed in SCD, Becketts and The Registry. Additions can happen. iI do collect non listed/recognized variants in my sets, but view them as extras.
The gray area for me comes when a variant gains wide hobby recognition but is not listed in one of those sources, such as the 52 House yellow Tiger. I collect those but do not count them as part of a master. Another gray area, applicable to the 1991 set as well, are stock color and back differences. In or out. Someone might say you need the red and black cards from the
1st series of the 1952 set, but do you need the 52 and 54 gray backs, or the 56, 59 and 60 gray and white backs, or the 53 white and black bios ?
Not attempting to be argumentative. Everyone can have their own view
. If a master set includes all variant cards, or cards that differ in any way from their counterparts, including unintended recurring or non recurring print defects, then I think there are exactly no master sets out there anywhere
