Sunday, however, the revered, still fleet-fingered guitarist who got his nickname from Sherlock Holmes' sidekick - "I always did like Sherlock's stories" - makes a rare appearance in Glenside at the Keswick Theatre.
The show, in which Watson will be accompanied by multi-instrumentalist David Holt, with banjo player Tony Trischka opening - is a benefit for the Philadelphia Folksong Society, which is putting on the 50th Philadelphia Folk Festival in August.
Taking a break from caring for Rosa Lee, his wife of 64 years, the octogenarian icon recently talked from his home in Deep Gap, N.C., about his memories of playing Philadelphia clubs during the folk revival of the 1960s, his favorite guitarists, and the state of his own playing nearly 80 years after first picking up a guitar.
Question: Do you remember your first experiences listening to music growing up?
Answer: My dad and two of my brothers worked for an uncle who bought a big old Victrola. And my dad and the boys worked half a week and he gave me that thing, and 50 records. Everything from the blues singers to the more modern music. I was 5 years old then.
Q: That would have been in 1928. What was the modern music? Al Jolson?
A: Right. You said the name that was just about to roll off my tongue. That, and mostly the black blues. I'm thankful that Dad wasn't a racist. My mother was, a little bit.
Merle and I, my boy, we loved the blues when we got into the music together when he grew up, we got to know and love lots of the people - John Hurt, and Brownie [McGhee] and Sonny [Terry], all those people.
Q: Great players.
A: Yes, they were. They treated us good. Some of the black players were a little prejudiced until they heard me and Merle do the sort of white version of the blues. And we didn't try to take anything from it or mimic the accent. I always sang in my own voice. Merle was a finger stylist on the guitar. Bless his heart, he was a brilliant musician.
Q: Did you teach Merle how to play?
A: I did not teach Merle, he just picked it up by himself. He picked it up, started to play it. He did it the way I did.
Q: How old were you when you first started to play?
A: Let me tell you a little story. My dad said, "Son, learn to play a good song and have it finished by the time I get back from work, and if you can play me a song and sing the words to it, we'll go to Wilkesboro tomorrow to a music store and we'll find you a little guitar."
That was during the Depression. He said, "I can't afford to buy an expensive one." . . . And he got me a little Stella guitar and I thought I had the king's treasure. I was 11 years old at the time. I played "When the roses bloom in Dixieland, I'll be coming back to you," the Carter Family tune. I could pick it and sing it. He laughed and said, "Son, I guess I'll have to keep my word, now, won't I?"
Q: You lost your sight as a baby?
A: I didn't know how I lost it. Let me tell you something strange. I went to the hospital and they took pictures of my eyes and blew them up. They found out that my eyes had been damaged by contaminated eye drops, the kind they use to cleanse a baby's eyes. They said they could give me 5 percent vision in one eye. I said there's no use crying over a glass of milk spilled in a sand box.
I was born in 1923. I've been without eyesight for as long as I can remember. People say, "How do you get around?" I can see with the feet and my hands and my ears. [Laughs.]
Q: You're known for your acoustic guitar playing, in both the fingerpicking and flat-picking style.
A: Yes, I do some of both.
Q: But before Ralph Rinzler, the folklorist, "discovered" you, when you were picking with Clarence Ashley in 1960, you played in electric swing and dance bands in North Carolina.
A: Mostly square dances is what it was. The band didn't have a fiddle player, so I played lead on a Les Paul guitar on all the fiddle tunes I could think of.
Q: But then when the folk revival happened, and Rinzler brought you up to play at Swarthmore College and the Philadelphia Folk Festival, you only played acoustic. Why did you quit the electric?
A: I didn't know enough about using an electric guitar except playing lead notes. I could play some of the Merle Travis parts. And when I played the lead guitar for the dancing, I did it with a flat pick.
Q: What do you remember about playing Philadelphia-area folk clubs like the Second Fret in Philadelphia and the Main Point in Bryn Mawr?
A: The Main Point was always a great place to play, they had good audiences there. And at the Second Fret, my friend [the late blues guitarist] Jerry Ricks used to prepare the food there, and then he would come out and pick with me sometimes.
Q: Who are your favorite guitar players?
A: My favorite was Chet [Atkins]. He's the guitar player of the century. Unbelievable, the things he could do with a guitar. Could play three or four parts at a time.
Chet and I did an album together. [Reflections, released in 1980]. I told him, "I don't want to do it, I'd ruin your album." He said, "No, we'll do it the other way around. I'll ruin yours." He didn't have a bit of false pride in him.
Q: How has your playing changed?
A: I think it's better than it used to be. There are people who would argue with me, that would say that it's not. But most people who know the guitar know that I can play better now than I could before. My finger style has improved 100 percent. I do sort of like Merle Travis did: I can do the rhythm and the lead finger style. That's a little hard to do.
Q: How's your health?
A: My health, for a man 88 years old, is exceptionally good. But my thinking - I'm stressed out. My little wife has been sick since last November. She had a stroke and she was in the hospital and now she's in rehab. We're trying to get her speech straightened out.
If I have to leave pretty soon, I've fixed it to be ready to go. I sit in my rocking chair in my family room and listen to Randy Travis and his song "Doctor Jesus": "There are so many out there . . . do you think you could work me in? I need you to mend my heart and save my soul."
Now you know how I think. I'm not afraid to die, son.
Contact music critic Dan DeLuca at 215-854-5628 or email@example.com. Read his blog at www.philly.com/inthemix.