David Willetts has written to a number of universities to lobby for the admission of his constituents. This strikes me as highly irregular in every possible way.
Firstly, the universities are autonomous charities not Government departments ultimately answerable to Parliament. Any MP has as much business writing on behalf of constituents to his(her) local university as he(she) does writing to the local Rotary club. Second, the admission of students is explicitly protected by law from political interference, so this is a particularly inappropriate matter on which to lobby. And thirdly it cannot be right for a Minister to act as a constituency MP within his(her) own departmental area as if he or she held no Ministerial responsibility. Ministers must avoid even the appearance of impropriety.
Finally, how could this have done any good? There is no way a university could lawfully take account of the ministers' letter in its admissions process so there is no way that the constituents could have been benefitted without breaking the law.
Its difficult to avoid the conclusion that Willetts was either wholly ignorant of the principles which ought to govern his (and the universities') conduct, or wholly reckless of the consequences when he wrote those letters, and 'wholly reckless of the consequences' are not comforting words to write about a powerful man.