"The (Jones’) Driver had been made by Jack White, one of the great club-makers of the day and winner of the British Open in 1904. Although the exact reproduction of all parts of the Driver was important, perhaps of more concern was the duplication of the feel Jones had for this club.
Fortunately, I had previously re-shafted this Jack White Driver for Bob, and so I knew the exact
requirements of the shaft, both in its rough and finished state. Even so, I had to go through 5,000 pieces of hickory before I was able to narrow my choice down to four shafts. By test and measurement, these shafts were the four most likely to reproduce the playing characteristics of the original.
They were worked down to exact micrometer measurements of the original, weighed for duplication
and tested for torsion, deflection and recovery.
Of the four, two proved to meet the deflection curve of the original, and, since they also matched the torsion requirements, were processed into finished clubs. (These two) were checked under various atmospheric conditions and one proved to be the exact duplicate of the original in every respect. It became one of Jones’ new set. I still have the other one as a memento of a pleasant task."
From the Modern Guide to Shaft Fitting