Even though there are many differences, there are several "common threads" that could be providing the tasting hints in common:
1. Grains ... even though they are different mash bills, they still use the same corn, rye, and malt supply ... jsut in differing amounts.
2. Water ... they use the same water supply.
3. Barrles/maturation warehouses ... although there could be differing proofs and locations, the barrels themselves and the general warehouse locations are the same.
4. Equipment ... they use much of the same processing equipment.
Perhaps this is a bit of terroir for the Jim Beam distilleries (at Clermont and Boston) ... or maybe it's just one of them ... and that's why it doesn't seem to be completely uniform.
"Remember, the BEST bourbon is FREE bourbon ..."
I know the flavor/funk you are talking of, I've gotten it from most of the Beam products, thinking back OGD 114 included. It seems to me to be a little bit of a malty thing, might go back to the common grain source/storage.
"I'm and optimist, even if the glass is half empty, there's still more in the bottle!!!!!"