Never, never, never, on cross-examination ask a witness a question you don’t already know the answer to, was a tenet I absorbed with my baby-food.
Do it, and you’ll often get an answer you don’t want, an answer that might wreck your case.
Stepping into a major trial is like plunging with a weighted belt into a dark and weedy pond. You manage to scramble up for air, but the rest of the world doesn't matter. And you always think you're drowning.