While I agree that filters are bad, in Shifty's case at least, the filters predated the OF.
Are we sure that this isn't just a game of telephone? The first mention of back issues here at least framed the breast reduction thing as a question and not as a statement from her. From what I remember, she spoke about a specific spinal issue requiring surgery which to my knowledge doesn't seem to gel all that well with the usual kind of complaints of muscle strain from poor posture that big tits tend to cause.