The ideal Firebird EA would be one that can make money in both a trending and ranging market. Reversing the signals will allow this EA to make a lot of money in a trending market obviously, but get killed in a ranging market. You can use an indicator to filter for periods of range and trend, but that would be too lagging IMO. Instead, after a series of losses in the range mode, the EA should switch to trend mode and look for opportunities. After X number of losses in trend mode, it switches back to range mode. I wonder if anyone has tried this. However, waiting for a series of losses before it adapts to the market may be just as lagging as using an indicator.