I have a 1969 Yamaha FG 12 string in which my neck bowed in 1970. I had a heck of a time finding someone who could fix the bowed neck. I was told later that the instrument should have been tuned down 1 step and capoed. I think that if I would have changed to lighter guage strings and tuned down the strings when I was not going to play for a while this might not have happened. What kills me was that at that time I could have spent $200 more and got a Martin.