Given that there was a vote in each country for devolution, I doubt even the most diehard Tories would be brave enough to rescind the will of the people. This posturing is much more likely to turn people against them, whereas if they actually starting performing as a government they may have some chance of convincing some people that they would be better off led by Westminster.
I don’t agree with Pantglas about Wales being glued to Westminster if there was a Labour Government, I think the last few years have been a massive eye opener for a lot of Welsh people, we are no longer willing to be sheep in the wake of England and will continue to do things our own way.