Broken Rocker Shaft Bolt Removal

I always make a good center punch just incase I later need a drill. Then I use wd-40 or similar ( in the textile mill we had very little more than 7-11brand spray solvent, more like brake cleaner ) as thread lubricant and begin the off center pecking in counter clockwise direction. I've backed out 100s of broken bolts this way. The "fixers" in various departments were good at breaking bolts. I recall walking by a fixer, opened my hand to show 5 short pieces of 1/4 inch bolts that were broken on a flange like shaft coupler. He says, "You a damn dentist or what?" My reply, " Or what I guess. Dentists use drills".