4109 Not a Black and White Decision by Brock. 2010-10-22

This was a real teaser from Brock. In a left & right grid, apart from 1 across, which was normal, each clue was really two clues, side by side, leading to two answers, one for each side of the grid. The difficulty came from the
18 clashes between across and down entries occurring in three consecutive rows in the grid. There were many variations but only two ways to get 18 clashes. The preamble gave a hint that solvers “should consider what might have coloured their decisions”. In one of the variations of entry the words BROWN & GREEN could be discerned and this gave GREEN FIELD SITE under STABLE, and BROWN FIELD SITE under BLOCKS. This also resolved the ambiguity of where to place HORSES and HOUSES.

 
Across
1 Rip up stalks and cobble where animals used to be kept (12, two words)
STABLE BLOCKS Anagram STALKS COBBLE
6 Detective’s vehicle: Yard engaged one for hire car (4)
BUSY BUS + Y (yard)
MERC 2 definitions
7 In the morning with island cut off, HE relaxed, ie, mooched so, irritated, SHE worked out (6)
AMATOL AM + ATOL(l) (He = helium)
COMODO Anagram MOOCHED SO less SHE
8 Oriental naval officer once led in revolt pursuing vessel our side trapped in long and thin rolling weed (6)
TINDAL TIN (vessel) + LAD reversed
KNAWEL WE (our side) in LANK reversed
9 Facial features hidden by greenish-blue head of hair with silver behind — an ugly old woman (3)
EEN Hidden
HAG H(air) + Ag
12 Ed’s first person, Bob’s last to follow Mat on stage (3)
WEB WE + (bo)B
LEG 2 definitions (ON + STAGE)
13 Local channels show disdain over broadcast with very loud hum (on STV?) (5)
REENS SNEER reversed
SOWFF SOW + FF (very loud)
14 With equal parts of eluant, detergent and starch added first, old-fashioned suit collars ironed, at last, flat (6)
ELDEST EL(uant) + DE(tergent) + ST(arch)
BEDSIT (irone)D in BESIT (to suit)
16 Genuine piece of writing from Brecht? If up for review in German, contemptuous comment results (4)
ECHT Hidden
PFUI Anagram IF UP
18 Little boy and little girl smuggled in load hauler transported for money (6)
LADDIE DI in LADE
HALERU Anagram HAULER
19 Wedges from scarlet bananas? There’s not a hint of red in bananas! Black needs to be removed from this fruit (6)
CLEATS Anagram SCARLET less R(ed)
ANANAS BANANAS less B (black)
20 Inns and halts stores to consume regularly more than one punch, perhaps with snacks, after half essentially is lost (6)
HOUSES USE in HOS (halts)
HORSES HORS (d’oeuvr)ES
 
Down
1 Bottom-feeding fish takes in gas from lake when there’s someone swimming around (7)
SUCKERS ER in SUCKS
BLATHER (gas) L in BATHER
2 Might this serpentine witch be fit for release as amiable individual following transactions in place of punishment? (5)
LAMIA Anagram AMIABLE less BE
TRONE TR (tranactions) + ONE
3 Mappers about to cut square bits from Tokyo in section to south of capital, local officials found (6)
OBANGS BANG in OS (Ordinance Survey)
4 Characters appearing regularly in court I’d admit fell wildly below acceptable, having fine slapped on old English hero (7, one entry is two words)
CUT DOWN CoUrT i’D + OWN (admit)
BEOWULF Anagram BELOW + U (acceptable)  + F (fine)
5 Green colour and slice of orange put in crushed ice — gallon of tonic friend served up with drop of Beefeater in thus? (8)
ECOLOGIC COL (colour) + O(range) in Anagram ICE + G (gallon) + O’ (of)
SYLLABIC ALLY reversed + B(eefeater) in SIC
10 Fine tiling being laid in ground cut up without spades, if it needs ground to be firm (8)
TESSERAE ESSE (being) in EART(h) reversed
DEFINITE Anagram IF IT NEEDS less S (spades)
11 One left after argument with old cow cross volunteer is able to duck imminent upheaval, perhaps (7)
BEEFALO BEEF (argument) + A (one) + L + O (old)
VOLCANO VOL (volunteer) + CAN + O (duck)
14 Unit in Palestine hands over American under extreme pressure to give out signal shortly to Church (5)
EPHAH EP (extreme pressure) + A(merica) in HH (hands)
BELCH BEL(l) + CH
15 Hemp plants son and I had since older big guys promote Ecstasy among teens (5)
SIDAS S (son) + I + ‘D + AS
ETENS TEENS moving E (ecstasy)
17 French article is not so much trouble if you guess conjugations at the ends of words (4)
LESS LES + ‘S
FUSS last letters iF yoU guesS conjufationS