varjag said:
If I recognize, say, a momental juxtaposition of people and/or surroundings I shoot instantly: such moments don't hold for long and any interaction would ruin them.
That is true up until you take your first shot, which by definition consitutes an interaction. You have to be able to see, focus and compose instantaneously in order for that technique to work, which beginners cannot easily or consistently do with a manual rangefinder. As far as I understand it, the decisive moment has a slightly larger window of opportunity, allowing you to study the scene and wait until all the elements properly fall into place. Seeing and shooting immediately requires a great deal of practice and most beginners will undoubtedly make errors photographing this way. In fact, most photographers will want to take more than one picture to increase the likelihood of getting a winner, especially if the people in the viewfinder are stationary.
In any case, your technique might work best when photographing a group of moving people in a public space, where none of them can be sure that you took a picture of just one of them. At the moment the first shot is fired, some or all of them will probably turn, look and see your camera - and the others. By not being able to deduce who was just photographed, they will probably continue on their way or simply turn the other way.
What do you do if you wish to take a second or third picture in rapid succession? Do you just fire away, even after your subjects have heard the first shot and turn to look?
By not communicating beforehand, don't you decrease your chances of following up with better pictures?
I do agree that your technique works best in a specific context, which seems to be the context you enjoy taking people pictures in. I cannot imagine using this technique, however, to photograph stationary people within 2 meters who do not look like they would appreciate a deliberate and unannounced photo taken of them.
Kevin