Tory Devolution

As Welsh Ramblings has highlighted on his blog the Tories have finally woken up to the issue of devolution, albeit purely from an English point of view. I wonder if as they have suggested that only English MP’s should vote on English only issues would the same be true on Welsh MP’s. When a referendum for a Parliament for Wales goes to the House of Commons will we only see Tory MP’s from Wales voting for or more likely against it?