Complex sentence: The song was once thought to be a song co-written with Charles Manson though this of course is false, though he did co-write one of the later Dennis Wilson compositions, "Never Learn Not to Love".
Split into simpler sentences: The song was once thought to be a song co-written with Charles Manson, though this of course is false. He did, however, co-write one of the later Dennis Wilson compositions, "Never Learn Not to Love".