I made the comment about not even being on for a minute because I was trying to make a point about the importance of the light being off.
@Sativa1970 Explained it best to me a while ago. A light bright enough that you can barely read a newspaper if left on all the time so the plants can adjust will be okay. And I am sure an occasional flash of light would be harmless. If not, no outside plants would ever make it to harvest. I recently read about someone causing their outdoor plant to reveg from a bedroom light being on too much.