Ken Clarke's return to the Tory front bench has been widely reported and commented on on the Internet. Apparently, his economic wisdom is boundless and will help right the wrongs of the British economy which were inflicted by Brown.
However, despite his seemly vast economic knowledge, according to the Tories, his opinions on the Euro are heresy, and something which shouldn't be taken too seriously since it's not something he would know about anyway. Pro-Europeanism and views on the largest project of economic integration in the world are also outside this economic genius' remit, as is anything that would challenge the Tory's conventional wisdom.
I mean, he would have to have been Chancellor once for anyone to consider his views seriously, wouldn't he?
On a serious note, I do think Clarke is a capable politician and minister, and he's probably a good choice for Cameron's shadow cabinet. He may hold views that go against the Conservative party orthodoxy, but I'd say that he'd toe the line now (or at least make more of an effort to) now that he's back in frontline politics. As a "big-hitter", he could be a very valuable weapon for the Conservatives.