Intensity masters need to only effect intensities. I was busking a show on sub masters the other day and hit the problem that I had an effect running on moving lights upon one sub master. Fading in another sub-master (say stage red state) over-rode the effect and stopped the movers because the movers had been set at home (with zero intensity) when the sub was recorded.
It also means that I couldn't have one submaster to trigger the effect and another to fade the intensities on the movers in - again that stopped the effect.
I can't see any use for that happening (yes the manual says it does that, but why????).
Andy