Sharpening brazed carbide bits

Reading through my 1940 Advanced machining handbook, there is a chapter dealing with the then new brazed carbide tooling. The recommended method for sharpening is , eg silicon carbide wheels and a hone with something else . They give the tool rake details as well which is handy. They also reckon you need at least a 2hp lathe with a rigid setup and at least a 14 " lathe and up to 20 hp is OK . The setup examples given include 1/4"depth of cut at 150 fpm and a fast feed rate too . They discovered it is great for machining hard cast iron but they were still experimenting to a point . Of all the books I have, this one is the easiest to get grips with . The brazed bits I have tried are rather dull out of the box . Is there a trick to sharpening them ? Mike