Everything is very interconnected. The underdose and overdose numbers are determined in isolation, just as any good scientific experiment should.

Casual observation reveals that vitamin D overdose results in hypercalcemia, a condition treatable by vitamin K. Vitamin E overdose results in hemmorrhaging, a condition treatable by vitamin K. There are no known symptoms of vitamin K overdose. Vitamin A overdose (from retinol) can be treated by vitamin E and vitamin K.

Magnesium is balanced with calcium. Sodium is balanced with potassium.

So naturally, I wonder what happens when you supply vitamin K in excess, then determine the overdose amounts for the other fat-soluble vitamins. Once that number is found, reduce the K by steps and repeat, until you have the recommended minimum ratio of K to the other vitamin.