There seems to be this almost superstitious belief in the so called MACD signal among the technical trading crowd. Below is a graph of the scaled tick data vs. the MACD Enhanced signal. The tick time series is scaled by subtracting the first value in the series from all other values in the series. This allows the tick series to be displayed with the MACD Enhanced signal.

Generating the Plot with GnuPlot

Generating the plot. The plot was generated with GnuPlot 4.2.3, which allows multiple axis plots to be displayed. To do the display:

set ylabel "scaled tick data"
set y2label "MACD Enhanced signal"
set yrange [-6:6]
set y2range [-1:1]
set autoscale x
plot 'GS.Jul_10_2008.signal' index 0 with lines axes x1y1 1, 'GS.Jul_10_2008.signal' index 1 with lines axes x1y2 3;

At least going by these charts it looks like the EMA is a better choice than the MACD Extended plotted above.