You may be on the right track with fuel burn, but only as a "gross error check". Know that this will also vary with cruise altitudes actually flown.
From a flight deck point of view, excess weight is indicated by higher pitch attitudes when flown with otherwise normal airspeeds on normal flight paths ie - normal glide slope approach /landing path segments.
Last edited by L-38; 2nd May 2009 at 15:30.