One problem with using inches, pints, and hectares is that federal agencies
usually require metric measurement. As well, publications often direct metric
for linear measurements. Another issue is that we are talking about pieces of
objects, not complete dishes, teapots, and full-length boards. I dont see
anything wrong with stating that "calculations based on the arc of a rim sherd
suggests this 2.5 centimeter long fragment probably measured 9-inches when
complete." In my experiece, federal and state agencies,  wanted distances measured in
metric to satisfy reviewing agencies. Instead of beating your breasts and
making "Custer's last stand" on this issue, why not find out what your SHPO
thinks on this issue and then ask the lead agency directing your client to hire you
what they want in your reports?

Ron May
Legacy 106, Inc.