I know they say carbon can't hold a bend but my Nacra 20 mast bends a little to port(I think) above the diamond wires. It does not really effect sailing, at least not my sailing. I think my mast spent a lot of time stored on its side in atlanta before I purchased it. I have often wondered if heat from the sun along with the way it might have been supported on its side could have altered the mast itself. But I can attest that there is a slight permanent bend. I'll see if I can get a picture to show you guys what I mean.