Jon,
Today's late day rally is a case in point. At 2 p.m. EST the 8,17,9 MACD and Full Stochastic, 14,3,3 most crossed over for a profitable long trade. However, the 12,26,9 MACD crossed over about ten minutes later, but the Slow Stochastic was already moving up. So you would have to wait, but there was no pull back, before the market began to turn down again at the end of the day. The down trend could have been traded profitably as well, with a coincident cross of the faster MACD with the Stochastic.
Chico