Ways to Undo Mistakes in Språng

I posted a short video of ways to get rid of mistakes made in a piece of språng.  In knitting you pull on the end and rip out your work, and in weaving you reverse what you did.  With språng I have tried that, reversing what I've done twist by twist.  Usually I lose track of what row each twist belongs to.  To preserve that information and thereby save time and aggravation, I put in something to open the shed in a row above the mistake.  Then I take out all the twists to that point but no further.

 http://youtu.be/EnchU2sIs1M