but a properly done weld tangent to the post should be as strong as the flat bar. Rudders built with SS posts and molded fiberglass skins are a problematic design - even if almost universally used. It isn't easy to get a good, permanent connection between the two materials, and almost impossible to keep the water out of it long term. Most of them last a long time. An all composite rudder doesn't have those problems, however a composite post does not fail "gracefully" by bending first, rather it will just snap off if it fails. Sometimes that might be good, other times, maybe not. On my rudder we ended the composite post about two feet from the bottom of the blade, on the theory that a really hard grounding would break off the bottom of the blade but leave the rest of the rudder intact. I'm not about to test that though, till absolutely necessary.