The live premiere was on a TV show. It was just James,
a microphone,
and an acoustic guitar. The second time was also a TV show; it was a live
show called "CMT Outlaws" on Country Music Television. Multiple songs were
performed, but unfortunately the performance of Mama Said was not aired.
One possible reason for it not being played often might be the subject
of the song. It is about
James and his mother, how he always wanted to distance himself from her and
then after
she died, he realized how much he took her for granted.
The song is kind of an accident - James originally wrote it for himself,
but when the rest
of the band heard him play it they insisted he put it on the album.
The video for the song was only released in Europe (Until the DVD was recently released with
all of Metallica's videos)
Most of the video is
just James singing
in the back of a car, but if you
pay close attention you can at one point
see the rest of the band
crossing the street behind the car.