Is O (4,6) like v (6,2,7) ??

Oh and is K Weekend?

Boolbar] I thought the same - but wouldn't the clue be in lower case, if that were the case? [MF] I'm still flummoxed by the 'O' clue but have a hunch it's more to do with numbers than letters.

What, Middle of Kelvins or something? Sadly no. Well done on K though.
[Chalky] Yes and no. Unhelpfully.

The Weekend one reminds me of one we had on Cryptic Stations which was e This was Mile End - though I, like Chalky was put off by the capitalization - and was looking for a "head" or "top" answer.
[MF] I thought Raak had got O - you're saying not ?

Nuts - that "head" was supposed to be hidden.

Crosswords are generally filled in in all upper case, so I think "K" is valid. For "bust down reason", would this be something to do with not wearing a bra? I can't think of a 9-letter way of expressing that though.