Yep, good to have some humoour on a Friday!
SPOILER ALERT
Can anyone help me parse 4 down - although I guessed it straight away and it helped me with 1ac and therefore the rest of the crossword - why is it "not art"?
BTW the whole clue is "This is not art, perhaps - and trained Tyroleans do it" (5) (I've got YODEL)