The presence of two recondite words at 4 across and 4 down means that this puzzle is going to find a few out – including me. I ‘resorted to aids’, as the saying goes, pleased to have the excuse of needing to post this blog to put me out of my misery. 26 ac also brought me up short – so all in all not my finest hour.
Across
1 ASIA – reverse hidden
4 SCHIPPERKE – CHIPPER inside S + K[or]E[an]; something to add to the list of famous Belgians?
9 THORN APPLE – hopplanter*; a prototypical ‘weed’ with white trumpety flowers and prickly leaves, called jimson weed stateside.
10 omitted – even those who wrote this straight in are probably not feeling especially this.
11 NOGGIN – N + going*; a snifter is a drink peculiar to ‘stage colonels’ such as Jimmy in Reggie Perrin and the major in Fawlty Towers.
12 AIR+CRAFT
14 CHAT – orwight my son? ‘chat up’ is slang for addressing a lady with a view to a conquest, ‘bird’ is slang for a young lady, and a ‘chat’ is a warbler.
15 COASTGUARD – runners as in smugglers.
17 GUIDELINES – GI around the bra of the social etiquette world (U) + DELIS around NE.
20 PS+ST – a post-script is a rider, as in a proviso or supplementary clause.
21 READ+JUST – I had to get this from the wordplay as I am unfamiliar with Wallace’s stuff; the book is The Four Just Men.
23 RHEBOK – herb* + OK; very much the bra of the antelope world at the minute, albeit in a different guise; watch out for ‘rhebuck’, which also pounds the African plains.
24 BOOM – double definition.
25 INORDINATE – the literal is easy enough, but the clueing is rarther canny: insubordinate minus the sub (editor).
26 SLEIGH BELL – Dancer is one of the bullies who became toadies after Rudolph’s elevation by Santa. A parable for our times.
27 omitted
Down
2 SCHOOLHOUSE – SCHOOL + H + OUSE; a fair few solvers will have been working around Peterhouse, Porterhouse, etc. and picking their brains for a specific college or uni.
3 ARROGATED – Harrogate minus H and plus D.
4 STANNIC – tincans*; I tries making anagrams from that and cansnot but all to no avail. Do I hear chuckles from Barsetshire?
5 HOPE AGAINST HOPE – title of a remarkable memoir by Nadezhda Mandelstam.
6 PIERROT – ERRO[r] in PIT; I happened to watch an episode of Men Behaving Badly in which the bloke who isn’t Martin Clunes was hamming it up as one of these characters, white gloves an’ all.
7 R+U+MBA – some won’t care for the airy-fairy literal ‘one from Cuba’, but since this is the bra of the Caribbean cruciverbal terpsichorean world I for one am cutting the setter some slack.
8 EIGHT – double definition: oarsmen and one way of saying the past tense of ‘eat’; I’m pretty sure I say both, though not at the same time.
13 FORESHOR[T]E+N[ot]
16 UMPTEENTH – putthemen*
18 LOUT[IS]H
19 STRUDEL – D in ulster*
21 REBUS – RE + sub reversed
22 ABODE – A+BOD+E, where the bloke must come before the E[uropean].  
I would watch out for ‘rumba’ and ‘samba’ being clued as computer applications. Rumba is a mainframe terminal emulator, and Samba is a Linux file server.
Anyone else a bit disturbed by the part-of-speech in 18dn? Probably just me because in the two possible sentences “X is ______”, the “is” is not the same usage. The stricter equivalent would be “being loutish”. But I’ve ridden that hobbyhorse before to no avail.
I do tend to get antsy when the commutation test involves two sentences using the copula. It’s so semantically slippery. Remember Anax’s argument (ST 4515) that “a doormat” = TIMID on the basis of the test “He is timid” and “He is a doormat”. I still don’t buy that on similar grounds.
More importantly though: how’s that Contreras of yours?
Edited at 2013-01-14 10:17 am (UTC)
Edited at 2013-01-14 05:57 am (UTC)
Also didn’t know RHEBOK but it was pretty obvious what was going on there so I wrote it in with some confidence.
I enjoyed the belated Christmas reference at 26ac and PSST.
I never read THE FOUR JUST MEN but like, I suspect, many of my generation I know the title well from the 1959 TV series starring Dan Dailey, Richard Conte, Jack Hawkins and Vittorio De Sica.
Edited at 2013-01-14 07:12 am (UTC)
I put SCHIPPERKE in eventually, and was slightly surprised to find it correct. Likewise RHEBOK, especially as it turned up (spelt better) in another grid very recently. Though the cryptic is precise and you can’t put the H in anywhere else, it’s a bit of a heffalump trap. THORNAPPLE also unknown, but two recognisable words from the anagram made it simple enough.
STANNIC from the Cornish parliament and Sn it might as well be the proper adjective.
All in all, a fine crossword – favourites included GUIDELINES (had to write out the cryptic bits until the penny dropped), SLEIGH BELL, UMPTEENTH for the slick anagram, FORESHORTEN for the highly misleading “not at first” and PSST just for not having any vowels.
Edited at 2013-01-14 10:12 am (UTC)
Like others didn’t know the dog and had to guess. Knew STANNIC (and as McText says watch out for stannous). For many years laboured under the mistaken belief that in the hymn “Jerusalem” they sang of “dark stannic hills”.
Don’t like “one from cuba” which suggests probably cigars – why not “steps taken to show resistance to university business degree”. Liked PSST
Loved the clues to 20 and 8. I’m less keen on “Korean regularly” for KE since one cannot determine regularity on the strength of 2 letters, since there is only one gap. Normally I overlook that when it’s every other letter in a four-letter word, commonly used, but when it’s just two letters taken from a five-letter word, far less common in The Times, it seems less satisfactory.
Loved NOGGIN and PSST.
COD to Eight because of the amusing “several in a row” defintion.
Like others I didn’t know the dog, or indeed the apple, the antelope (spelled like that), STANNIC, the requisite meaning of BOOM, or the Wallace book. Or indeed Wallace, come to that. Oh, and I think I knew there was a place called Louth, but not where it is. It’s a miracle I finished really.
FYI, ulaca, the bloke who isn’t Martin Clunes in Men Behaving Badly is called Bob the Builder.
The perpetrators of bob the builder on the other hand should be arrested, for giving an entire generation of children an utterly wrong idea about how builders go about things, which only bitter experience will corrrect
There was a young woman from Louth
Who returned from a trip to the South
Her father said, “Nelly,
There’s more in your belly,
Than ever went in through your mouth!”
So not all our GK comes from a classical education! Ann
Edited at 2013-01-15 10:34 pm (UTC)