RE: CRASHED plane due to servo chatter!! :>(
I use a Y-harness and extentions all the time and haven't had a problem. I only use JR and Hitec. I did once have a issue with a Y-harness that I took out of one of my crashed planes. ( Y-harness wasn't the cause) I put it in a new plane and when ever I gunned the throttle the ailerons started dancing uncontrollably. It took a while to find what was wrong, so I just replaced it with a brand new JR Y-Harness and she was good as gold. The problem: The Y-harness was pinched behind the glow tank causing a light short, and when I gunned the throttle- the vibration increased causing the servo's to dance. Make sure non of your wires was pinched. If you had a complete short or a broken wire, they would have not worked at all.
Digital Servo's like to dance a bit, but that's normal. I believe it wouldn't be the cause for your crash.
Pete