Tom,
I have been stuck using yardage graffiti because it is unavoidable, at least in the US. It is too ingrained in me to look and use it. I purchased one of the first Bushnell's back a little more than a decade ago, to help in analyzing and documenting the various hickory clubs. I approached it the same as anyone else here would, trying to create a direct comparison to an equivalent contemporary club. It took expressions of disappointment from British Golf Collector members while playing over there, to get me to to play by feel/eyeballing it. So it took a little kick in the butt to see the error of my ways and I truly thank them for it.
I don't expect anyone else to play this way. I just want to do my part to keep it alive so it doesn't get lost to history. Playing the entire game by feel gave me insights to the clubs that, if I had continued in a modern mechanical fashion, I would never have experienced. Unfortunately for others to duplicate what I have found will take a serious time commitment and a wordy description will not get it across.
With regards to the Society of Hickory Golfers, they have no real authority yet. Guidelines on play are just recommendations that sponsers of events can follow or not. The "rule" that would be of interest here is that they decided that the current year USGA rules should be followed, for early 20th century events. There is, as expected, a waiver on the equipment in that anything that was used, even clubs that became ruled illegal, can be played with. It was decided it would be too difficult to have people play by rules from the era because; as quickly as the rules were changing between 1898 and 1931 we would have to decide on one particular year. Plus, people typically don't know the current years rules so expecting them to sit and learn a new set of rules would be almost impossible. The 19th century events are different in that there are only a couple of events for that era and the gentlemen running them created a set of rules based on a combination of rules from the existing clubs, and it is short and easily remembered.
Hope this clarifies things.