No, I think we may be in agreement. I think the relevant point is whether Ts in the hand written recipe refers to teaspoons or tablespoons. Teaspoons would mean only 10% salt by weight - which seems more plausible.
That said, it also occurred to me that this whole "11 secret herbs and spices" deal is probably the biggest marketing red herring of the modern age. If KFC - at any time in their history (because I think KFC used to be better back in the day) - left out any, say, two of the herbs, nobody would ever notice.