  Theoretical predictions for B decay rates are rewritten in terms of the
Upsilon(1S) meson mass instead of the b quark mass, using a modified
perturbation expansion. The theoretical consistency of this expansion is shown
both at low and high orders. Our method improves the behavior of the
perturbation series for semileptonic and nonleptonic inclusive decay modes, as
well as for exclusive decay form factors. The results are applied to the
determination of the semileptonic B branching ratio, charm counting, the ratio
of B -> X tau nu and B -> X e nu decay rates, and form factor ratios in B -> D*
e nu decay. We also comment on why it is not possible to separate perturbative
and nonperturbative effects in QCD.
