i always thought this cutting effect was done with a fader or a button like a transformer scratch pad.
first off this meowbay guy, i think he's from germany - is a bloody genius, and it was so cool to see the edit tape play as you hear the audio to really see what editing was all about back in the day.
http://www.youtube.com/watch?v=fziSqCUoVok&feature=related
check out the effect right at the 5:00min mark...
all you see is white tape = wow!
was all these type of effects back in the day done like this? i always thought it was done from the master track mixing board.
i think this is guy is amazing and wish these recordings were released on 12";
this was my fave edit mix
http://www.youtube.com/watch?v=rXEBDCX_O6M&feature=related