There is no Holly Grail in the world since market is keep on changing, but the cycling characters of the market is also a fact. Especially Forex, not like Stock market, it is hard to manipulated drastically by any individual(I know some brokers may do some tricky stuff, but believe me their business wont last long if they keep on doing that, as well, their manipulation is relatively minor compare to what ppl can do to individual stock....), therefore, it should be more predictable compare to later.
You are right, keep on adjusting is very necessary for an Auto system. In fact, able to adjust according to market condition and cycles should be one of features of any great auto systems.
At last, investment is an art, should never be gambling! :)