I would also never kill a pigeon with a bent keel. I have had many good racers with bent keels and personally i think it makes no difference. No good though for shows.
Blue Petra - broke keel 2 weeks before first YB race 2008 - performances during yb season - 1st section E, 4th NIPA Open, 3rd section E, 10th NIPA Open, 5th section E, 40th NIPA Open, 24th section E, 154th NIPA Open up to 27,000 birds.