I can (or could in my more limber days) demonstrate how to move relative to the other guy, but it's a little difficult to describe.  The easiest way to learn is to get a pair of one-handle stunt kites and chase each other. 

I remember reading an article about how line tangles happen but most important how to get out of the different types of tangles without crashing.  Does anyone have an idea where to start to look?  I thought I made a copy but I can not find it. 

I had a little diagram in the Flying Models combat column  a few years ago.  Essentially its:  if you are on the left and your plane went under untangle with an inside AROUND the other plane.  Left-Over-Outside   Right-Under-Outside  Right-Over-Inside.  This of course assumes you actually see the tangle coming and can see how you got into it.  If you do get into a tangle and can't figure it out.  Then the only thing to try is flying around each other a couple times in one direction.  If that doesn't work, switch and go the other direction a few more times and hope.

That is what was fun about watching the Minor Lads/boys(can't really call them boys as they are very fine young men) flying their F2D planes.  Almost every flight was a match.  Lost count how many times I thought I seen a tangle in progress and they would fly out of it.