i know about the article that said if you have a spell equipped in the off hand you wont be able to block. but my point is more directed to not having anything equipped in that hand, or having another weapon in that hand. i would think that you could still block.
and i can understand the reasoning behind the spell in off hand cancelling block because you can make a stronger block with both hands holding the blade than one. in most cases if you try to make a strong block with only one hand on hilt you stand the chance of loosing your weapon or being knocked off balance.