I will balance my bow on the fulcrum point when tillering, but like PatM said one limb could be much denser than the other...Might work with cookie cutter bows of glass, but when working with staves you gotta take what you get...You might get lucky though...I can see where an extremely heavy limb vs a light limb could cause some timing issues...I think balance on the draw and shot are more important, but I can see where equal limb weight would be great also...
Don