Duke, I just wanted to let you know how much I have enjoyed your lessons.  I particularly liked your little discourse on what constitutes playing the blues from the guitarist's perspective in How Long Blues Lesson #5 ("The VALUE of the note").  Not an easy thing to put into words.  I was also going to ask you a question about your picking style.  You tend to use top-down picking more, particularly when you want a staccato effect, switching to alternate occasionally when it is more efficient.  Is this a conscious choice or something that you just do naturally?

My picking style is a subconsious thing. I only learn what I do by people pointing it out to me actually. Picking is my weakest thing and i suppose if someone gave me advise on improving it when I was young I'd be a better guitarist. Now that I incorporate more jazz into my playing, the picking is the thing that holds me back the most. It's not easy to speed up your picking technique at 63!

No kidding.  I'm 62 and trying to learn alternate picking and using my pinky to correct bad habits I picked up over the years.  I actually like the sound of straight down picking for some licks and I see that BB King uses a similar picking style to yours.  I also notice that you use vibrato sparingly which gives it more effect.  I think vibrato is overused by a lot of modern blues guitarists (and singers as well).  Just my opinion.