I saw Blythe Danner's hair in the FOLLIES revival, too, and I found it got in the way of her performance. I'm SERIOUS!
For those that saw it, she had a lovely soft but full and fluffy bob in the show, and there was obviously not enough hair spray on it because she CONSTANTLY kept fluffing her hair back with her left hand. It became very distracting after awhile. I first thought it was just something she was doing for her character, but then when she started playing Will's mother on WILL & GRACE, I noticed she did it there, too.
In recent years, she's permed her hair so it has enough stiffness that she's not constantly having to blush it out of her left cheek all the time. I really prefer the soft hair, but if that means she's going to have to brush it away every ten seconds, then keep it permed, dear Blythe.
I must also add that I think she's a marvelous actress and was one of the strengths of that underwhelming FOLLIES revival.