Sorry, but I have to call BS here.... most popular lemon oils or "fretboard conditioners" such as Kyser's "Lem oil" or Stella-Harmony Lemon oil are almost pure lemongrass oil, which is chemically about as close to perfect as it gets for this application... I have no idea where this myth originally started (it´s been around for ages), probably from some douche putting Lemon Pledge on his guitar and trying to cover it up with a lie....