How many sub / subassemblies are enough?

Just went through the tutorial videos and a thought went through my mind. I wonder how many of you maximize your sub assemblies /subsubassemblies and to what level? Viewing the video on the wind gauge I would have thought that the blade/arm would be a pre assemble in fabrication and so why not a sub assembly also?

(note to video developer....the animation is backwards.)

Thanks,

Richard

SolidworksAssemblies