Thanks to Hamilton. Definitions are underlined in the clues.
Across
1 Cell is helping to get the go-ahead (8)
PLATELET : PLATE(a helping of food) + LET(to get the go-ahead;to be allowed to).
Defn: … found in large numbers in blood.
6 Sweepers made from brushwood? (6)
BESOMS : Cryptic defn: Implements for sweeping;sweep-ers made from twigs;brushwood.
If I’m right, this isn’t very cryptic.
9 Penny-pinching, vacuous young son goes back to pocket money (6)
STINGY : Reversal of(… goes back) [ inner letters deleted from(vacuous) “young” + S(abbrev. for “son”) ] containing(to pocket) TIN(slang for “money”).
10 Big gap in short shorts Versace designed (8)
CREVASSE : Anagram of(… designed) [ S(abbrev. for;short “shorts”) + VERSACE ].
I couldn’t find an example of the usage of that abbreviation.
11 Island group heard to mention cases (10)
SEYCHELLES : Homophone of(heard) [ “say”(to mention) + “shells”(cases;the outer covering of, say, shellfish, bird’s eggs, nuts, etc. ].
Defn: … in the Indian Ocean.
12 Mineral doused in formic acid (4)
MICA : Hidden in(doused in) “formic acid“.
13 World order mistakenly comes across as without cares? (6)
COSMOS : Anagram of(mistakenly) [ “comes across” minus(as without) “cares” ].
15 Engineers ring for curative (8)
REMEDIAL : REME(abbrev. for the Royal Electrical and Mechanical Engineers, a corps in the British Army) + DIAL(to ring on the phone).
18 Called over when signal done badly (8)
BECKONED : BECK(a signal;a gesture requesting attention) + anagram of(… badly) DONE.
20 Cult over to open residential area (6)
SECTOR : SECT(a cult;a small group of people having beliefs regarded by others as strange) + O(abbrev. for “over” in cricket) + 1st letter of(to open) “residential“.
21 Times of the topsy-turvy game maker (4)
AGES : Reversal of(topsy-turvy) SEGA(the Japanese video game developer;maker).
23 German nobles have their own cake (10)
BATTENBERG : Double defn: 1st: A German noble family, once rulers of the Grand Duchy of Hesse; and 2nd: … purportedly named after the family.
25 Work-shy pupil at lecture’s end succeeds one in command (4,4)
BONE IDLE : [ L(letter displayed by a learner driver;pupil) + last letter of(…’s end) “lecture” ] placed after(succeeds) [ ONE contained in(in) BID(to command;to order someone to do something) ].
26 Dances once left out of training grounds (6)
GALOPS : “l”(abbrev. for “left”) deleted from(left out of) “gallops”(training grounds for racehorses).
Defn: …, popular in the late 18th century.
27 Dirty mongrel found initially in South Yorkshire (6)
SMUTTY : MUTT(a mongrel;a dog of no definable type or breed) contained in(found … in) 1st letters, respectively, of(initially …) “South Yorkshire“.
Defn: …;obscene.
28 Crown protection for gondolier? (5,3)
STRAW HAT : Cryptic defn: Another not quite cryptic clue, based on a particular sense of “crown”.
Down
2 Methodologies without good backing should be flexible (9)
LITHESOME : Anagram of(should be) “methodologies” minus(without) reversal of(… backing) “good”.
3 Cordial working with Troy in charge outside (5)
TONIC : ON(working, as with an electrical appliance) contained in(with … outside) [ T(abbrev. for “troy”, the system of weights for precious metals and gems) + I/C(abbrev. for “in charge”) ].
4 Gamble for every relative amateur (9)
LAYPERSON : LAY(to gamble;to lay a bet) + PER(for every;for each) + SON(a close relative).
5 Delicate problem needs someone who’ll please (7)
TICKLER : Double defn.
6 Platforms twice supporting royal (5)
BIERS : BIS(a musical direction to repeat;play twice) containing(supporting) ER(abbrev. for “Elizabeth Regina”, leading royal in the UK).
7 At Pam’s disco dancing is intermittent (9)
SPASMODIC : Anagram of(… dancing) PAM’S DISCO.
The clue could do without the first word, using “disco” as an adjective.
8 See 14
14 , 8 What the group singing “Sugar sugar” wanted to do? (4,5,5)
MAKE SWEET MUSIC : Cryptic defn.
And the song “Sugar Sugar” was an example of bubble-gum music.
16 Today’s way of keeping in touch with errand-boy? (9)
MESSENGER : Double defn: 1st: A Facebook app and platform for, well, messaging your contacts.
17 Approach rear of abbey to move religious works (9)
APOCRYPHA : Anagram of(… to move) [APPROACH + last letter of(rear of) “abbey” ].
19 Is in two minds about changing musical instruments’ cover (7)
DITHERS : “zithers”(stringed musical instruments) with its 1st letter(…s’ cover) replaced(changing …).
22 Young man to clean train (5)
GROOM : Double defn: 1st: … and brush the coat of eg. a horse or dog; and 2nd: To train;to prepare someone for a particular purpose or activity.
23 One’s no hero to a child (5)
BADDY : Cryptic defn: As a child would refer to the antithesis of a hero.
24 Regulation achieved through legislation (2-3)
BY-LAW : BY(achieved through, as in “he made his fortune by being unscrupulous”) + LAW(legislation).
I didn’t really get the cryptic bit of 6a either, and it didn’t help that the only sense of BESOM(S) which I knew was in describing a lazy or disrespectful woman. I also couldn’t parse SMUTTY, being stuck on ‘initially’ referring to ‘mongrel’.
Overall I found this on the harder side with some complicated clues such as for BONE IDLE and unusual words such as LITHESOME. There was a mention of (the very appealing looking – thanks for the pic) BATTENBERG cake on an episode of ‘Midsomer Murders’ I saw recently which helped with what would otherwise have been unknown.
Maybe not very exciting but I like both the word and concept of a BADDY.
Thanks to Hamilton and scchua
Thanks H & S; Think 22d could be a triple def. young man; clean; train. Could not get biers nor parse bone idle.
I kept trying SCREW CAP at 28A.
I think that 6 across may be referencing the two meanings of BESOM. In WordPlodder’s derogatory sense a woman may be ascribed a lowly occupation such as being a sweeper.
Thanks Hamilton and scchua
Found this to be a good challenge with a couple of new terms in BATTENBERG and TICKLER (as a ‘delicate problem’). Also had to look up to see that gondoliers did indeed wear a straw hat. Had heard of an actual race meeting referred to as the GALLOPS, but not the training grounds as such.
Am with john@2 with the triple definition at 22.
A couple of subtraction anagrams at 13a and 2d were unexpected from this setter, with the first one taking quite some time to see through.
Finished down in the bottom half with GROOM, the tricky to parse BONE IDLE and BADDY (which brought a wry grin when the penny dropped).
Was convinced 27ac was “scurfy” – cur for mongrel, f for “found initially, inside SY…
I was shadowing this one – scchua & I share the Tuesday blog-slot – and I’m glad this week’s wasn’t mine. I always find Hamilton’s clueing slightly itchy; for example, I’m definitely with George @6 on SCURFY, which was the better fit for the clue, and confirmed by Chambers, so in it went & slowed up the SW corner considerably. And I agree about the crypticism of BESOM; BROOMS (in the sense of wood from the gorse) was again equally valid. ‘Short shorts’ is another case in point; obviously, ‘S’ is (very) short (indeed) for ‘shorts’ but, conventionally, ‘short’ is an indicator for dropping just the last letter of a word, I think. It’s not as though Hamilton can’t do it when he’s a mind: ‘One in command’ (= B[one]ID) in 25 is a thing of beauty.