Early, it has been suggested that Keplerian flows should be unstable regarding shear instabilities. This hypothesis, not seriously considered nowadays, is strongly sustained by a recent re-analysis of experimental data on shear flows and new laboratory experiments. We review some consequences on steady state accretion dises of a viscosity law derived from shear experiments. In particular, we show that it wholly suppresses the thermal and viscous instabilities within the radiation pressure dominated region, unlike the standard theory.