I have also just gotten bored silly, listening to her whine about how she got screwed out of playing Julie in the M-G-M version of SHOW BOAT (the part that went to Ava Gardner). Sorry, Lena, but you didn't get screwed out of the role. The part is not that of a black woman, but of a black woman who PASSES for white! So stop belly-aching about losing a role for which you were never right in the first place. There was no veiled racism, there was no studio politics, you were just wrong for the role. Simple as that!
I think you're missing a big part of this story. MGM sure thought she was right fo the part of Juile when they highlighted her in their 1946 film "'Till the Clouds Roll By".
Lena's MGM contract was up in June 1950 and at the same time she was blacklisted as a communist sympathizer; she also revelaed that she was in a mixed-race marriage - illegal in CA.
Since, as you said, Julie was a part for a black women who passes as white, it would seem Lena was perfect for the part.
Since MGM had a pratice of editing out black numbers from films released in the south, they could use Lena in speciality numbers, but probably hadn't the courage to use her in a lead. This isn't latent racism. it's blatant racism!
I saw Lena in LA in Pal Joey (1978) and she had the body of a sexy siren (and she was a grandmother of 61)!
der Brucer