Reform steps -- number of time steps to take before reforming the stiffness matrix. The standard Hughes implicit algorithm calls for this to be 1. When using the iterative conjugate gradient solver, there is no advantage to setting it to any value other than 1. When using the direct solver significant time savings may be realized by setting it to a modest number such as 5, but be warned that this is a heuristic shortcut that is without rigorous justification. The stability of the time-stepping ordinarily guaranteed by the implicit scheme may not be assured if this is set > 1.