Generally - no. Subarus (mid-70's IIRC) used to have gear driven cams. It was truly bullet proof.
Unless you make the gears out of plastic like Ford and GM have done in the past. When I say gears, I mean made out of real metal. Only our automakers can take a bullet proof design, like gears, and make it so that it is likely to fail.
Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')