This has me really excited about a possible solution. Can you confirm exactly what symptoms you had and what device you were using to control the P3 when you got the "disconnected" issue? I'm going to try this as soon as I get home now! Fingers crossed!
Symptoms were just random disconnects (not "No signal or low signal") it would actually say "disconnected" - And it would not reconnect unless I closed everything down and reconnected.
To be fair, I think I did have one disconnect after I did the re-link - BUT it recovered itself and reconnected in about 10 seconds without any intervention from me..
Last week I flew the Phantom for several hours straight and did not have a single disconnect.
Might be a coincidence that it worked for both of us.... but then again, it can't hurt to try. The other thing you should definitely try is changing out the cable - again... can't hurt.