Isn't it going to make it harder for him to do anything interesting with the short-termism review? I share the view expressed by some others that the nature of the review - ie not being carried out by an external 'big name' - meant it was unlikely it would go off-piste anyway. But he might have got away with something interesting, on the basis that many Tories are pretty ignorant about these issues and so may have assumed it was just dull technical stuff (Nu Dave not exactly known for love of detail I believe).
Now that Cable has outed himself as wanting to cause a bit of trouble (and as someone who likes to be highly thought of) the likelihood of sneaking some radical stuff through must be diminished. If I were a Tory concerned about the Cameroons tacking too far left (ho ho) to placate the Libs, I would be watching Cable like a hawk and finding reasons to oppose anything he put forward that looks even slightly radical.
Off course, this is all predicated on the assumption that the review was likely to go anywhere interesting anyway. I do not share the view that Saint Vince is particularly on the Left. Anyone can slag off bankers and their pay - even Gideon does it now and then. And the gap between Vince's 'anti-capitalist' conference speech and the actual questions in the short-termism review was rather significant. Unfortunately some people would rather take the speech rather than the policy proposals as the indicator of where Cable-ism sits on the spectrum.
I still hope that the review does come out with something interesting, and some of the questions it asks are definitely worth asking. But only if you think such reviews rationally weigh the pros and cons before reaching policy proposals, and are never subject any political interference, would you consider that the likelihood of major reform had not reduced.