Not sure what you mean by cross overs. They don't cross over each other. The Oscillator can rise while the Summation is falling (like now) but when it crosses the zero line it will turn the Summation positive.

One of the great things about these indicators is the Oscillator (NYMO) often gives advance notice that the turn in the Summation (NYSI) may be coming.

Whatever you are trading needs to have one or the other or both of those on your side. Don't fight either of them because they will punch you into the ropes and drop you on the mat.