Lucas-

Just another piece of information to have, I would think it would make for a more accurate yield measurement since volumetric measurements (Lexion) are affected less by variation in flowrate than mass measurement devices are.  The kicker is you need a testweight coorection, which the mass measurement would provide. 

We do try to store as much high protien, high testweight grain as we can on farm while shipping the common wheat to town at harvest. Having that information continously in the field would allow us to make an accurate decision on a truck by truck basis.  There are times we see significant differences in testweight within the field. 

I've also often wondered if there was a linear or inverse relationship between test weight & yeild within a field.

Are you coming to Oklahoma in Feb?