There's a great story about the composer Mozart. When he was 7, he accompanied his governess to the bazaar in Vienna. There was a band of street performers playing slightly out of tune. Overcome, young Mozart fainted. I can't claim to have such insufferably perfect pitch, but (perhaps because I play mostly clean) I am constantly "sharping out" any strings lighter than 11's - at least to me even if nobody else can hear it. I confess to playing a lot of acoustic and can't get away from the tonal qualities and lower action with 13's on those, so strength isn't an issue.