Sheared Woodruff Key on crankshaft

Just wanted your guys thoughts on how to remedy "minor" damage to end of crankshaft due to a sheared woodruff key.
Zed1015 (thanks Rob!) suggested I use some fine valve grinding compound and carefully lap the rotor to the taper.  I spoke to a owner of a local
motorcycle repair shop and he agreed with that procedure. I have already bought 2 new woodruff keys online.  I am attaching a few pics.

Jim
 

Here is a pic of the other end of the rotor.  The Woodruff key came out fairly easily and is shown above in 2 pieces.

After seeing the pics i can say that the damage is minimal and some carefull lapping will sort that out.
Just lap the bare minimum to get a smooth surface but don't try to eliminate all annular grooves that may be present .
Over lapping will move the rotor inboard slightly which can cause the starter gear to bind and you will have to lightly face the dished rubber damper that sits behind to regain clearance.
Some fine emery or wet 'n' dry on a flat surface or mirror can be used to reduce the dampers thickness if needed.