Taper Tip Steel shafts

Can a certain flex of taper tip shaft be used for a different iron to give other flexes? For example when I cut a TT S-Flex for a 3 iron, it is the same cut as a R-flex 7 iron. It makes sense to me then that a S-flex taper tip 3-iron shaft would be R-flex if I put it in a 7-iron.

If that is the case, is R-flex two inch increments (4 club) from A-Flex, like the R/S relationship or is it 1 inch (2 club) like the A/L?

This is all based on True Temper Shafts.