When I think about it, the green line could be used when starting a whole new long or short. The system can be improved in that regard. An advanced trader can completely exit shorts and start longs when the green line reads above 0.00 and price is above EMA 20.
For the basic system (especially for new traders,) only the red line's readings are essential.
For the basic system (especially for new traders,) only the red line's readings are essential.