Posted by R. Berg on December 31, 2000
The Origins section has nothing for "hard act to follow." I've always assumed (no, of course an assumption is not evidence) that the phrase originated with vaudeville entertainers who competed for places on the bill of a variety show. They had a saying "Never follow an animal act." Acts featuring trained dogs, trained seals, and so forth were so appealing that the audience would experience whatever came next as anticlimactic.