Just a note - if you printed this off (as I did) before 12 noon it might be an idea to revisit the Guardian site, as it has been updated (eg 4 down now shows as (3,3) rather than (6) which is what my printed version still had.
Really? 15D, presumably, if the word counts are right. But then what's the clue for 14A, and what's the clue for 15D doing there? Is it a straight swop?
I had a quick look over lunch and did a few answers but haven't worked out the 30 thing yet (group of brass monkeys lacking vitality (4)). The only answer which sprang to mind after this morning's fiasco had 5 letters...