Campbell was a bit of "stunt casting" He was popular entertainer at the time. (Much like Ricky Nelson in Rio Bravo)
Except
RICKY comes across laconic in
RIO BRAVO, and in that wonderful, but silly Western, it works;
GLEN CAMPBELL's performance in
TRUE GRIT (which I think is the superior film) is merely tolerable, and though
JOHN WAYNE is the one we came to see, in one of his very best roles,
KIM DARBY seems almost tolerated (I mean, is she likeable?) but
really carries the viewer thru the film. For me,
TRUE GRIT probably ranks as an "endlessly watchable" film, but I'm very interested to see the remake.