Vibrations will damp faster in wood than in hardned steel, however this is not the dominant effect in controlling how much shock you feel, technique plays a much larger role as well of course as overall functionality, handle issues and such.
The method described above minimizes the shock by directly reducing the amount of damping your hand does to the vibration of the blade, you can reduce this down to nothing by altering the amount of follow through. On a pure snap cut the vibration is next to nothing as the grip is very loose and there is no effort made to power the blade into the material being cut.
Jeff Randall has described many times a similar method he uses for large machete work. It is near identical to the method described above simply with a larger arc which would be of no benefit to a smaller blade due to its much lower moment of intertia.
The main problems people usually have is lack of technique, my personal problems are I over squeeze the handle and fatigue my grip really quickly, and drive too much with my elbow and fatigue my bicep really fast as well. I have to concentrate not to do this, it comes from habit of not chopping in this manner at all and the built in reflexes are difficult to overcome.
Your comment about hammers was interesting, from memory I recall a majority of Estwing used for heavy construction work. I did a quick poll the other day of relatives who still work and out of the dozen a vast majority used the large metal hammers (10). However personal bias plays a large part here in general they are held in very high accord around here so not using one is looked at as having inferior equipment.
In general though it would seem to me that hatchets would lose out to decent chopping blades in conditions of high fatigue or injury as in general the cross section of an axe head is much more obtuse than a blade and thus needs a much greater momentum to chop into a piece of wood equally. With very nice cutting knives you can make decent penetration with very little effort, the same effort with an axe barely cuts into the wood.
You can see this readily comparing a decent khukuri to a large bowie. For example, in order to get an 18" AK to chop as well as a BM I have to drive from my shoulder in a wide arc, as I progress beyond this the AK pulls significantly ahead. However if I used lower powered techiniques like driving from the elbow, the AK falls behind the BM, if I just use wrist snaps it falls even further behind.
Thats rather an interesting point you brought up, I think I'll do some with the the Granfors hatchet and probably the PAB from Strider when I get a chance and see how the relative ability changes as different techniques are used.
Anyway, the bottom line of course is do whatever works for you with your blades.
-Cliff