  We demonstrate runaway evaporative cooling directly with a tightly confining
optical dipole trap and achieve fast production of condensates of 1.5x10^5 87Rb
atoms. Our scheme is characterized by an independent control of the optical
trap confinement and depth, permitting forced evaporative cooling without
reducing the trap stiffness. Although our configuration is particularly well
suited to the case of 87Rb atoms in a 1565nm optical trap, where an efficient
initial loading is possible, our scheme is general and should allow all-optical
evaporative cooling at constant stiffness for most species.
