This approach won't work if you live somewhere windy^ - the cables will chafe and even with the nylon spacer, will likely short and/or electrify the soffit with

This approach won't work if you live somewhere windy^ - the cables will chafe and even with the nylon spacer, will likely short and/or electrify the soffit with obvious associated risks. ^source: first hand experience, albeit with cuphooks rather than magnets.