The ASL congregations have been doing this for years...reminds me of what my grandmother said about using the testimony cards
A brother went to the door and handed the lady his testimony card...she read it and assumed he was deaf and started signing to him. The brother ran off the porch and back to the car rather than say he wasn't deaf............
BTW even when I was a "faithful" jw I would never have taken this to the door.
Supposedly the cards and the phonographs were used because most jws had little skill talking to people. When the training program started, the cards and phonographs were no longer used. Is the WTS saying the jws are dumb now or the people at the door. Jesus and the first century Christians did not need any fancy devices.
Cellphones, texting, put a barrier between people really connecting and sharing ideas. Maybe the WTS wants to give a semblance of connecting to CYA.