Walter, That's the point. Personal satisfaction is the most important thing you get out of street shooting. I'd go even further and say that anyone actually able to give up street photography after discovering the satisfaction you get from it wasn't a genuine street photographer to begin with. As you pointed out, not only does successful street shooting not involve setups, it doesn't depend on planning. What it depends on is looking -- and being able actually to see that sudden situation you're talking about that just has to be captured. You're right: there's nothing "sophisticated" about it. It's the photographic equivalent of automatic writing. You don't think. You see and you respond.
Can these two things, discovery and abandonment, coexist in this context of artistic ability and achievement?
As far as the next idea: Adam and Eve, then?