I just found the mother load of bugs. All SI Enchanted versions of normal weapons except silver and daedric do not ignore normal weapons resistance!!! While this should be something for the USIP, I figured Mobs could handle this as the USIP is not maintained anymore.
Apparently I was under the impression that all enchanted weapons ignored normal weapons resistance, this is not true at all /biggrin.gif' class='bbc_emoticon' alt=':D' />