New Musical Instruments #3:
THE JAZZ PIANO CHOIR by Joel Sattler
Sight reading is the ability to play a piece at the first reading of the music.
The Jazz piano choir makes use of this technique.
The choir is composed of at least ten singers who can sight-read music [one for each finger!]. The actual player is the pianist, who improvises the piece, which is translated into sheet music instantly, which is read by the choir members and sung as as "scat" [nonsense words].
I would guess that the player would have to be in a soundproof room, so as not to be distracted by the singers, who would probably need a lead time of a few seconds to read the music as they sing it.
If the pianist was playing with a group, would the group be in the booth with him? Or would they be with the singers? Or both?