This is really one of the most ridiculous get-out clauses, because it is so wide. The whole point of the FOI system is so that we can see precisely what is being said in these discussions, and to find out what companies are saying behind closed doors - and what ministers are replying. Although it's laudable that the Department for Business Innovation and Skills got in touch to correct its response to me, it's rather rich to do so and then simply refuse point-blank to release any of the information it has just found.
The only consolation is that whatever Microsoft whispered in the corridors of power to de-rail the move to ODF - since I hardly imagine it was a fervent supporter of the idea - it didn't work. However, there are doubtless many other occasions when it did, but we will never know. That's just unacceptable in a modern democracy.