Eliza, Question 17 on the Welsh version of the census asks whether you speak Welsh. Hence it is not required to be answered by those living in England- nothing suspicious about it, and easily discovered by a simple Google search.

Having found a great deal of fascinating information about my ancestors from research using previous censuses, I am very happy to fill in the current census accurately; as has been said above, there's nothing asked for that you haven't already given to numerous other people who asked for it.

Disrupting it or filling in rubbish is not going to save anyone any money, nor is it going to prevent any of the information already in the public domain being there.

Alan says: why not get a computer that can collate the information they already have.

Err, really? How much would that cost then?