As the Guardian of the Ringstone, I've had many occasions to talk about the technique of splitting stone with an elegant lack of effort by understanding the crystalline structure of the rock and using the mechanical advantage of [a hammer and] wedges. A wedge being a form of lever where a long easy travel in one direction is complemented by a small powerful force at right angles. As Archimedes said, you can in theory move the very earth with a long enough lever and a place to stand. I've been a teensy bit obsessive about this craft on The Blob. One of the keys is to practice until you don't have to look at your hands, With a hammer and cold chisel, you must have faith in the hammer; if you check up on it, t'bugger will hit your chisel hand out of spite. I think it's probably true that, like Zatoichi, a blind rock-splitter would be as good as their sighted peers . . . not least because they will listen / hear better to know which wedge needs to♬k-to♬k rather than to♬k.Tally Ho apparently, true of the sounds made by hammer on caulking iron. You can hear whether the oakum is tight in the seam. As the caulking progresses - best carried out with a meitheal - the hull gets drum-tight and sounds it. If the hull isn't drum-tight, the ship will take in water and the mariners will have to pump instead of dancing horn-pipes in the off watch. As we saw in February and in contrast to Gertrude Stein's "a rose is a rose is a rose", hammers is a broad church to comprehend very large differences in purpose. Caulking hammer's head is made of a hard heavy wood the business end of which is bound by a metal band. The head is split along it's length to better absorb the shock of each blow and protect the user from white-finger and other repetitive-shock injuries. A by-product of the design is that it acts like a tuning fork and the pitch of the hammer will change as the working face gets worn away and the peculiar g=head gets shorter.
In the cited video, Leo makes the case that the caulkers mallet is not retro hang-over from by-gone times. It is an exquisite tool designed by insight, trial and error over many centuries: each part works synergistically not only with the other parts but also with the operators hand. That was my experience when I was using a tradesman's hammer in a peculiar craft. The binding of an old book is a thing of beauty even if you can't read. What I learned over 4 years of Tuesday evenings in the bindery of the university library is that each aspect on the binding enhances the function of the whole. The book opens to be read; but stands upright on a shelf; it can be packed tight; a single index finger can pull it from the shelf without destroying the spine. Leather, acid-free paper, cotton-thread and a bodkin, cardboard and cloth if engineered together properly [a hammer helps!] will be fit-for-function for 1,000 years. You can't say that about your iPad or my Yaris.