My opinion is it is Ok to taper the top of the T section within the allowed limits of the overall runner, in other words it can me tapered to match the wood body. Minimum thickness at the leading edge 1/4″ (E.2.i); minimum radius on the leading edge 1/16″ [1.6mm] (E.9) – this would apply to the top of the T since it is more than 3/4″ [19mm] (E.9) above the ice.
