Thanks for your response, Alan. I find it so interesting that whatever the mikes were like back then, they were apparently very successfully hidden. How distressing that modern mics have been so readily accepted as something we're "not supposed to see" yet are often glaringly evident on too many foreheads. Clearly, the sound designers won the battle over the costume and wig designers.
And not be argumentative, but there are so many production photos of Streisand in FG, and her gowns for People, You Are Woman and Music That Makes Me Dance are all quite low cut in the neck line.....can it really be those photos are all from staged photo shoots where the mikes could be removed? That's still a bit of a mystery to me.