I certainly like to check the meter on a known energized circuit first, although I hace to admit to not rechecking after testing the dead circuit.
I'm reminded of an article many years ago about the inspectors that used to walk every mile of track on the London Underground (subway) system every night. Apparently they would always climb down carefully onto the track and connect a box containing 12 bulbs onto the conductor rails so they could see when the control center switched off the power for the night.
Asked why so many bulbs, one said "With one you could have a dud bulb. With 12 you have a better chance."
"But what if there are 12 dud bulbs?"
The reply sticks in my mind:
"Mister, if you're that
unlucky, you're not going to be living much longer anyway!"