Reasons suggested are that he wants to spend more time with his family (never true), that he wants to spend more time on his family firm (might be true, it's a lucrative operation making industrial clothing) or that he wants to "concentrate on mapping out an alternative vision for the future of Conservatism" (in other words, counter his party's Euro-sceptic stance). The Diary could not run any of these tempting options past Mr D as his office said he was "making no comment at the moment".
Instead we are left to muse why this intelligent and personable politician has made so little impact shadowing education. The answer may be that no Tory could have made much headway, either in Parliament or in public, against a formidable David Blunkett with full Prime Ministerial backing - and quite a few Tory policies in his locker.
But who will take on the education brief in the reshuffle now expected at the end of May? The Diary has a sneaking desire to see Ann "Scourge of Howard" Widdecombe in the post. Who then would seem fiercer on homework and discipline, Mr Blunkett? But the rumour mill says Mr Hague has to balance his Shadow Cabinet by replacing the left-wing Mr Dorrell with another figure on the party's left. Time to bring back Tim (family values) Yeo.
* ETHICS AND SEX
THE Catholic church is in a bit of a tizzy over an apparent clash between high ethical standards and sexual morality.
The Council for Catholic Maintained Schools warned a school head in Co Tyrone that it was investigating a complaint that he was living, unwed, with a woman, despite his obligation to promote the Catholic ethos in the school.
Tom McKee, the National Association of Schoolmasters Union of Women Teachers' meticulous regional officer, decided to do a bit of research, checking the council's guidelines to school governors.
Imagine his delight when he read the section on possible conflicts of interest for governors. Section 46 requires governors to declare any family interest; this includes "if they are husband and wife or living together as husband and wife". It then refers to "co-habitees" twice more.
A CCMS spokesman was quick to see a distinction. "Governors don't deliver the curriculum that promotes the Catholic ethos; they oversee it," he explained.
Excellent though it is to have such watertight protection against nepotism in these post-Nolan days, it seems a fair argument that if the Catholic church permits saucy geese on boards of governors it can hardly complain about a saucy gander on the staff.
* NAKED AMBITION
ALSO IN Northern Ireland: a small town is reeling from the incident on World Book Day when an - extremely tall - 14-year-old ambled into his all-purpose bookstore with his pound;1 Government book voucher tucked insouciantly into his pocket. His idea of an improving tome? An (attempted) purchase from the top shelf.