How much does centre of gravity change when a shaft of different weight is added.
Length of shaft is so important as to keeping heel and toe aligned.
As irons are graduated by weight a move in weight or length of shaft must effect centre of gravity would that be true.
Would you need to take 5g of the head if you added 5g to the shaft?
Do OEM give what weight shaft that robot testing is done with their irons.
Life is not easy for me needing 1inch longer and 2 degree upright.
Swingweights and dead weight are a nightmare.