For the benefit of those who are defending it, here's what Q magazine had to say about Paul Simon's Songs from The Capeman in their list of the 50 Worst Albums Ever:
The musical based on a Puerto Rican gang member's life was Broadway's biggest ever flop. Salsa singer and future Mr. J Lo Marc Anthony was aiding and abetting.
That's weak sauce. It doesn't say anything at all about the album.
OK, so the show was a flop, but so what? I've heard flops with good
scores, and hits with crappy ones.
I myself have not heard the album, so I have no opinion one way or the other. I would suggest, however, that the presence of one good song on an album wouldn't necessarily be enough to keep an album from being one of the worst albums ever; I might even argue that an album with one good song is inherently worse than one with none, because of the squandered opportunity and/or talent that one good song represents.