Quote from FrankSlaughtery:
sma's are useful for me in setting stops. the only indicators i have on my charts are the 20, 50 and 200. for example, if i see a stock rose up to its falling 50 dma i'll short it w/ a tight stop (1 or 2 atr). and most times when the stock blows past my stop it keeps going. like the phrase from failed moves come fast moves.
obviously moving averages mean nothing in sideways markets. if i see a stock stuck in a range i won't even look at the sma's b/c price doesn't respect them. there are plenty of other stocks that are trending either up or down to trade.
re exponential or simple sma's, in my experience it really doesn't matter which you use.
lastly, never try to optimize your sma setting. for example, don't look at one setup that worked perfectly using a combination of the 4, 17 and 89 period sma. i only use the 20, 50 and 200 b/c they are the standard ones.
oh, one more thing, institutions love to buy on pullbacks to the 50 sma. but after price drops below watch out. for example, aapl closed below the 50 sma on 10/5/12 at 652. it then fell to 505 in less than a month and a half and never going above the 20 sma during this period.