Ally -
I've played the blues while thinking of nothing else but the sadness in my heart, letting my fingers move wherever instinct and the spirit took them; and I've played the blues properly, thinking about and playing only those notes that correctly fit within the standard C, F and G chord progression.
With the latter, the results are always good, and I almost never make a mistake; but if my wife is in the same room while I'm playing she just goes about her business, barely paying any attention.
With the former, the results are very uneven, and I make many mistakes, and I sometimes get lost and can't find my way back; but on occasion, when it all somehow comes together, the music is as great as I can play it, and my wife, in another room, has stopped dead in her tracks and come in to listen -- the soul of the blues coming through.
PS
(A rough analogy only, of course: I have neither the 'natural' spirit of Old Tom or Eddie Hackett, nor the 'normative' abilities of Colt or Mackenzie, both of whom had magnitudes more skill/talent at golf course architecture than I have playing the blues.)