Only Redford refused to say the line.
He even made sure to have it crossed out in the working script."
So how could Hubbell be?"

Robert Redford and Barbra Streisand in ‘The Way We Were’.Everett
The book, which includes exclusive interviews with Redford andBarbra Streisand,delves deep into the protracted behind-the-scenes drama.
It also alleges that Streisand was “infatuated” with Redford from the moment they met.
Both directorSydney Pollackand writer Arthur Laurents spoke about Streisand’s crush on Redford.
It was hard for women not to have a fixation, because he was everywhere, like Elvis.
He was the golden boy long before Hubbell came along."
According to Laurents, “She was simply mesmerized by him because she found him so beautiful.