noticingthemistake - I wouldn't say lemon oil is bad used sparingly. I wouldn't recommend soaking the fretboard daily as SLY is doing. Rosewood is natural wood - and wood soaks up oil, from fingers, polishes etc. I've seen alot of guitars and necks get "dark" from oils etc...not that it hurts the guitar. I think the only harm is the "gummi bear effect" - if the fretboard becomes greasy or sticky over time from too much application.