I've never been hassled about my Swiss Army knife, scissors, or exacto knives.

However, last year at FCO, Delta security refused to let me take a mezzaluna on the plane in my carryon bag, and wanted me to check the bag. Like I - a 5'4" middle aged woman - was going to run amok with a two-handled vegetable chopper? I told them NO WAY would I check the bag, having just spent the previous weekend luggageless thanks to their baggage handlers. So I was allowed to check the mezzaluna separately.

I never saw it again.