I thought these paragraphs from the Live Theatre UK review about Shuffle's second act are especially insightful:
"In the second Act, the characters cope explicitly with the ways, the many ways, in which the White world has exploited and assumed the treasures, glories and specifics of the non-White world. A section involving George Gershwin is both sobering and astonishing.
In a very dramatic and powerful way, the second Act blisteringly establishes the gulf between what white people make of the performances of black people and reality, and the ongoing pain experienced by black creatives struggling in a white world. Porter and Ashmanskas are particularly electric here, in words and action; equally, though Stokes Mitchell and McDonald, through silence, convey decades of shared pain, gestalt grief.
The presence of four true, great, black Broadway stars on stage as these climactic scenes play out is magical - and harrowing. Just them being there, with their shared skills, genius and status clear to all, lends authenticity, proportion, and deeply resonating honesty to the experience that plays out."
Begin at the beginning and go on till you come to the end: then stop.