One Effective Acting Technique

I recently had my first experience on set with a movie star who asked the crew to all "hide away," clear his field of vision, and not look at him.  If they weren't someone who would actually be in that experience in real life, he didn't want them visible while he was acting.  That meant the monitors and every single station for every department, which were all set up on the side of the set he was facing, had to move and hide.... I'd look over and see ADs and PAs hiding behind pillars.  Today I learned that this actor has done theatre before -- I'm curious how that worked.... Does that mean that the stage manager has to have a table on wheels and roll around so that they're never in his field of vision during rehearsal?  Maybe have a desk set up on a bike and just pedal around the rehearsal room?  And the crew in the wings... Do they have to wear costumes?  I'd love to be a fly on the wall in that tech....