I read the response letters. They were very thorough. I imagine it was because the responses were meant to be public...
But in reality, you don't have to respond at all. Or if you want:
-----------------------------
Dear Mr Lloyd Cedars,
I will not retract anything I said. If you want to take legal action, go for it. Make sure you sue in my jurisdiction. I welcome the opportunity for discovery, and the opportunity to appear before a neutral party. I would absolutely love to play your video, again and again, in a public forum for a permanent record. Official documentation that your penis is beyond control. Also, if I'm forced to defend against a real legal action, you can be sure I'll counter for all my legal fees.
Now, please go play hide and go fork yourself.
X0X0,
<name>