This series was a noble endeavor on Olivier's part, but "Come Back, Little Sheba" was its least successful effort. He is far too old, and approaches playing an American as an acting challenge. He isn't at home in this world at all. Woodward is not at her best and Fisher was never known for her acting abilities. It's a flat interpretation.
The play is far better represented in its film version, and held up beautifully in the MTC revival of around ten years ago. I did not see the off-Broadway version earlier this year.