THE HILARIOUS ANNUAL COLLECTION OF READERS' LETTERS THAT WERE JUST TOO LEFT - FIELD, OUTRAGEOUS OR WITTY TO MAKE THE PAGES OF THE TELEGRAPH. 'SIR - Two days of news about the Duchess of Cambridge, and you haven't yet told us about her hospital gown. Who designed it? How much did it cost? And has she worn it before?' 'SIR - Sede vacante has not a...