I don't sub but I use subs. These days I write out a chart for almost every single song, no matter how simple to make it as easy as possible for the subs.
This was after I played with the world's worst sub. My regular bass player was out, but my drummer said he knew someone really good. My drummer is really good, so I figured, OK. The sub didn't want to do a paid rehearsal, but I insisted. It's a good thing too because, he hadn't spent even a minute going through the material. Immediately after the rehearsal I wrote out a chart for everything and sent them to him. We played the gig and I don't know what the hell he was doing, but he was just really awful. I don't think he played a single song correctly the whole night and I'm talking about 12 bar rock songs like Great Balls of Fire, Chuck Berry's Carol and other songs with three chords which repeat the same pattern the entire song.
Fortunately the club manager loved us and we have been playing the club regularly ever since. It just proves that song selection is everything. But I can tell you that I'd cancel a gig before I'd play with that horses posterior again. The only funny part is that he was over on the other side of the stage acting like, "Yeah, I've got this. I'm all that and a bag of chips." Well, he wasn't even the bag of chips.
Can anyone tell that I'm still mad about that?
I hear ya.
The one and only time I got to play at the Hole in the Wall in Austin, our regular drummer couldn't make it, so he hooked us up with someone who "was great!!" The guy was like, "Nah, we don't need a rehearsal, i listened to your songs and I got it."
Nope, he didn't "got it". The worst part was after our set, the manager came up to me and one of the guitar players and said something like, "I was hoping to get you guys into a residency with us, but I don't know...."