Hi Chris,
I've no time for this stuff logically, but I can see cyclical activity ... you might find that a turn occurs every x days, but that the turn is either not there or too small to bother with 30-40% of the time say. Then you add a not unreasonable few days either side of the predicted date as nothing is perfect, throw in the difficulty of being sure it's a top or bottom (only when it starts to reverse will you be sure - that might already be too late) and you're imitating Christmas Turkeys again.
I'm happy cycles can be found, I don't think it's anything to do with planets or anytthing else like that - it's just that the underlying machinery hasn't been identified, possibly it's something we're simply not mentally equipped to understand yet (try teaching a caveman relativity, now throw in the distinct possibility that the Universe has either 11 or 26 dimensions and let me know how to figure out the distance between two points in 11 dimensional space....) It's entirely possible that things like planets just happen to move in such a way as to approximate the underlying mechanism, or are doing so for a while - pure coincidence could be all it is.
I think it's far more likely that time's running backwards and good traders are simply the small fraction of the population who can remember being older than that a ball of gas, floating 600 million km from the Sun, is doing anything other than helping stop Earth being hit by comets. (Which, admittedly, would probably affect the markets quite dramatically).
Astrology etc is barking up the wrong tree I'd say - if you have something that works, and it's down to reading tea leaves, then you need to dig deeper... how on earth will you know it doesn't work any more otherwise? You just KNOW that the day it stops working is the day you are getting deeper and deeper in the hole and becoming uncomfortable about the act of faith that is telling you it'll all turn back up shortly...
Dave