Mass produced chisels are induction hardened. However, they are done on a conveyor belt traveling by the coils, maybe stopping briefly.
Some interesting things happen using induction heating. First, the variables for getting consistent heating change. Part shape, travel speed past/through the coil, and the power to the coil become the variables to sort out and control. A way to measure temperature is important too, but temperature is the result of the above variables. The chisels travel past the coil at a fairly constant rate, and have essentially the same geometry, which allows this to be an automated hardening process. Oh, and they're all made of the same steel too. If you can control these variable carefully, it could be viable. I've read some people love the forges, but they don't try to heat treat with them, and the coil size limits using them to weld damascus as well.