The point that Thal makes is a good one. The goal is to be able to play whatever is set in front of you, whatever piece of music you have your heart set on. With this in mind, the way you get there is irrelevant, just so long as you get there..
Experimenting and finding out what best works for you is indeed a logical approach. You can denounce technical exercises; Hanon, Pischna, Czerny, Cramer, Dohnanyi, Liszt, Brahms, and all the others that conceived them, but that's not going to do you any good. For the beginning pianist, technical exercises must have some merit at developing the hand and allowing the student to perceive how the hand moves across the keys. That does not mean practice technical exercises religiously and never resort to pieces. On the same token, that does not mean practice only repertoire and burn every technique book you can get your hands on. Your analogies to musicians and drugs is just as poor as Thal's analogy with smoking.
How can you say that practicing technical exercises, scales, arpeggios, runs in thirds, sixths, etc. is a waste of time? When you think about it, the exercises are just like etudes. So I guess that means that the etudes of Chopin, Liszt, Debussy, and Rachmaninoff are all a waste of time, since they don't really develop anything, and since there's nothing to develop, the only things you will get out of them are tendonitis and carpal tunnel.
You can't say that technical exercises are the root of all playing problems, and that they are responsible for all injuries. Improper piano playing causes the injuries, regardless of what literature of music you decide to set in front of you.