I see.Well, it's one perspective on improvisation, of many. My experience is somewhere in between. For songs i know well, melody and all, i am not really thinking as much in chord/scale relationships but letting the melody guide me as to where to go, and simply hearing nice melodies in my head since the tunes harmonic progression is so ingrained. For songs i might be playing for the first time on the spot, yeah i might fall back to chord/scale relationships just to get through the tune and deliver an acceptable product.
I did not make the original comment though, but was merely backing it up with some context. I think most here would agree with the concept set forth by Hal, he's a guy that undeniably knows what he's talking about, you'd be a fool not to listen.
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