Back in the early 1960's, I believe there were two different bucks (not the Foster buck) taken from the Catoosa WMA which actually were entered in the B&C Record Book.
I believe we saw a few larger antlered bucks back then for a variety of reasons, but here are my top 3:
1) Lower deer densities which provided better quality food sources (per deer).
2) Less experienced, less effective hunters, who typically would shoot the first buck seen, rather than high-grade antlers.
3) In this general region, the soil is apparently a bit higher in the nutrients more conducive to larger antlers than compared to many other areas of TN.
Of course, in times past, there was also a very short gun season with a 1-buck limit in TN.
(And, no, I don't not want that.)
What baffles many, has been the lack of agricultural crops in the more rugged "plateau" regions of TN. Agricultural crops (and rich bottomland soils) seem to go hand in hand with those areas in most states consistently producing the highest scoring antlers. But that said, the 12-point mainframe Foster buck, nice as it was, having a score of 186, it would still be dwarfed by many 10-point mainframes scoring over 190's in states like Illinois, Ohio, etc.
Many other states are consistently producing mainframe 10-point typicals scoring over 190, and they're doing it now. That never happened in TN. State to state soil differences are likely the main reason why.
By comparison, most bucks which have made B&C in Tennessee have been somewhat freaks of nature. Even a perfect 12-point mainframe buck is somewhat a freak of nature.