[BadaBing]

A few years back I needed to drill out alot of screws for a glass and aluminum railing. To cut down the workload I ordered several left handed bits. They cut in in a counterclockwise rotation.
The advantage being that the heat and torque of drilling, stepping up through s everial bit sizes, caused many of the bolts to loosen un enough during the drilling process that some of them did not require an easy out and those that did came out much easier.

Now, when needing to drill out a bolt, I make a poi t of us I g the reverse twist bits for my first few steps.
And let not forget generous amounts od on blaster.