I agree with most of what you say. The damage thing is worth thinking/worrying about if you are bashing your buttons all day, but your running analogy is poor (and what do you mean recent findings? surely anyone who has ever run knows landing on your heel is bad?). Your efficiency arguments are irrelevant, no-one runs out of energy pressing fire.
The argument wasnt about Damaging your fingers, tendons..etc. That would only be an issue, if your job were to non-stop rapid button presses.
The argument was about speed and fatigue. As member '1500points' has pointed out, (snicker) trying to play a rapidfire game results in major fatigue. If you use a leaf button, that fatigue level goes down to almost nothing. And to be clear, fatigue with micros on rapidfire games can set in as quickly as 30 seconds. Where as the same player, could play for an hour, and still not be fatigued with leafs.
As for the ball - heel stuff... Id only heard about it within maybe the last 10yrs, on a documentary featuring the Tarahumara tribe, (I believe) where they run barefoot for like two days, going 200miles, without pause. They filmed the runners on a treadmill, and made the heel realization. The resultant research, has been slow to spread... as a lot of people still are clinging to the 'dont run, it will mess your knees up', research that predated it. And when looking for the tribe name, found an article from 2010, talking about recent discoveries to do with barefoot running. So... while it may be obvious that landing on the heel isnt great... the science is / was still figuring out all the details. Without looking yet, I have a feeling your a younger person. Young people seem to think that anything thats 2yrs old is ancient. When you get older, you will understand the relative reality of time much better. China has a recorded history that goes back over 2000 yrs... and USA, only a few hundred. Tv, was made in 1911. Its a modern invention... but only a mere blip in this billions 4.5 billion year old planet.
http://en.wikipedia.org/wiki/Tarahumara And Randy has some very valid points.
For example, Defenders 2 way leaf stick, is very short. The shorter the throw, the quicker the reaction times. Longer handled sticks, require more travel before activation. This can be the death of you, esp. on games like defender.
And Leafs are not the only reason why a true Wico 8 way will beat out modern joysticks for certain games. One factor, is the rubber centering grommet. It allows a perfectly balanced pivot point, and there is no major spring bump tension to overcome. It also has a circular outside path, which is needed for robotron.. to roll effortlessly from one direction to the next. Some sticks have a square path, and you would get stuck in the corners. (delay from clashing into a dead stop, and then changing direction) And then of course, its got less distance to activation than many micro based sticks. (and thats before you adjust the leafs)
Many of the popular sticks, like the Comps, (as far as I could tell last I looked) use a spring systems which alters the position of the pivot point. The shaft sort of slides a little to one side. This causes even more distance to travel before activation... and throws off the feel of stick. The newer japanese sticks use a ball pivot, which is much more true... however, you would still have to deal with the clicky heavy tensioned micros, that also have that slamming collision impact. While the collision of a joystick isnt that fatiguing, its still slightly discomforting. You may not consciously notice it... but once you play a game with real wicos, its like a slap in the face. Just smooth silky movement, without that jarring slamming.
Admittedly, they are a little stiff feeling.. but that somehow doesnt matter as much as the slam stuff does... and the other benefits, such as lightning fast response times.
While it may be true that masters can play Robotron with micros (id be curious to know what stick... cause I cant play it with comps, nor supers).. the average joe may not be up to the robotic task of strategies needed. Instead, we rely on being able to do on-the-fly action... and as such, need every millisecond worth of advantage. That games projectile speeds, and ferocity, pretty much require it. Again, the smooth feel also complements it as well.
I can honestly say, that I used to hate leaf buttons and sticks. Even, and especially when I managed an arcade. They needed adjustments and cleaning often. And, I really didnt know about the floating stuff either. It wasnt till near the end of my arcade days, that I made some realizations. I replaced the Galaga with Micros, and quickly found out, that Id made a big mistake. And later, found a real Defender, and Robotron to play.. and again, got schooled.
Newer does not necessarily mean better. In fact, these days, quality has slipped drastically.