...that I manually tagged all 16 discs of Wagner's Ring Cycle - where each CD has about 20 tracks each, all with names like "Dritte Szene:Vergeh, frevelnder Gauch! -- Was sagt der? -- Sei doch bei Sinnen!" only to find out that due to some bizarre printing/encoding/work experience cretin-based error, the track names didn't necessarily correspond to the music. I don't speak German, but you know something's up when Albrich the dwarf enslaves his diminutive bretheren with a yearning soprano duet.
There are so many lessons to learn from this sad tale. The greatest I think, is: Make sure walls are not load bearing concrete before you punch them.