The SEC may not play great Defense but their defenses are also facing the best offensive skill players and QBs. It's not all that difficult to play D in the B1G West. Or in the East when you're not facing Ohio State, Michigan, or PSU.
SEC fans seem to indulge in a lot of chest-thumping and self-congratulation regarding their unparalleled successes in football. You would think that all that winning would engender a certain level of self-assuredness. And yet a single post from a lowly B1G fan regarding SEC defenses can apparently cause a fair amount of southern-fried teeth-gnashing. I must say, underneath all the bluster and bravado they seem a bit thin-skinned and insecure.