This is indeed one of the most bizarre issues I've heard. 8 strings breaking?? I wouldn't rule out some kind of paranormal activity there... I think I broke about 8 strings in my whole life! lol Seriously, though, I've never heard of a guitar that breaks strings like that, not even on very poor fret leveling jobs. The crowning is essential for a good tone, and also to prevent the 'blade effect' that @Redhouse mentioned. But even then, it's hardly enough to break so many strings in a row, unless the strings are already a bad batch... But then again: strings WEAR FRETS out! They are much, much stronger than frets. Some minor sharp edge that could only be seen with a giant magnifier wouldn't be cutting through strings like butter! It's insane! I've seen frets that were rough and sharp like powertools, and they didn't eat strings like that... The only explanation that sounds reasonable to me, other than aliens or a curse, is a combination of many factors mentioned above, including (slightly) bad strings, all lined up against you. Maybe there is a curse involved after all... Btw, I've never met someone who LIKES flat frets, only people who don't NOTICE how bad they sound. I did many fret leveling jobs when I started messing w/ guitars, but always neglected the crowning because it's time-consuming, boring and required an 'expensive' tool I didn't have. However, my guitars sounded like bees, no matter how much setup I did. Eventually my brain worked, and I figured this crowning thing was a thing for a reason.