Mystery solved:  When I shortened the lan cable, I neglected to check the pinout, assuming it was standard.  I inserted the new connector with the following pinout: wt/or,or,wt/gn,bu,wt/bu,gn,wt/bn,bn.  Unfortunately, the original connector on the other end was: wt/gn,gn,wt/or,bu,wt/bu,or,wt/bn,bn.  I made the two ends match, and now the rpms register properly. Is it possible that "Lug" had a similar problem?

In any case, thanks again for your prompt responses.