[carmine]

I bend the rotor tab just enough so that when I place the distributor cap in place
it will sit about 1/8 inch above distributor.

In other words you should be able to push cap down in place and when you let go it should spring up about 1/8 inch.

This tells you that the rotor tab is positively contacting the carbon tip in cap.

No arching can occur between rotor tab and carbon tip if they are in positive contact with each other, which equates to minimal wear over thousands of miles.

The brass tab at end of rotor arcs across the gap between brass tabs at each plug location on cap. It's these tabs that wear long before you could wear out the carbon tip in cap.