Dan posted an article in which that is explained. My explanation is a little simpler. If you take gold at $250 and the dollar against the Euro at $.80 = 1Euro (the conditions about a year or 18 months ago), and then you take where I think that the dollar will end up bottoming, around $1.18=1 Euro, gold then should be at $369 (when we get to 1.18 which we are not). The market however discounts this move in advance and accentuate it (thus we had a spike to around $391). Now we are simply retracing some of that premature spike. Once the market starts to fear, let say $1.25 or lower for the dollar, another move up in gold maybe even above $400 (but just a spike) may occur, and if the miners make new highs on such a move, it may indicate that the move has further to go, my guess is that for the near future (like a yea or so) the $400 will serve as a barrier, and the miners are just going to attempt their recent highs but not much more. I doubt we go much under the major support at $330 or so either, so we have an excellent trading range to play with here.
Zeev