Mephisto 3048 Paul McKenna – Saucy Postcard Edition

Some help needed please parsing 7A, 21A, and 27D.

Some diverse GK required from Edwardian postcards to Narnia via a Waggle-dagger apple.

In the clues, definitions are underlined. Wordplay explanation is followed by very helpful comments.

ACROSS

1 This is missing pocketbook for machine which screws up? (8)
THREADER: TH(is)-READER; pocketbook=READER;
7 Gent is full of it and can go forth (4)
STIR: S(‘T)IR; “can” doesn’t appear to serve any purpose?
10 Redolent of English case (9)
EVOCATIVE: E-VOCATIVE;
11 Stay for opening of Parliament (4)
PROP: PRO-P(arliament);
12 Charles and one Commonwealth economic association (7)
CARICOM: CAR-I-COM; Charles=CAR; Caribbean Common Market;
13 Discount place pictured by McGill? Time to enter (8, two words)
SET,ASIDE: SE(T)ASIDE; reference Donald McGill (1875 – 1962) an English graphic artist whose name has become synonymous with the genre of saucy seaside postcards. “Do you like Kipling? / “I don’t know, you naughty boy, I’ve never kippled!”
15 Flourish of letter with frame circling (5)
SWASH: S(W)ASH;
18 Pleasure carrying about Mr Tumnus or his ilk (4)
FAUN: F(A)UN; Tumnus is a fictional character in the Narnia books
19 Potentially big lad or I should be shut up (8)
GAOLBIRD: (big lad or)*;
21 Troparion about parent who’s close? (8)
CATHISMA: CA-THIS-MA; not sure I understand cryptic;
22 This African language we hear in railway junction (4)
KROO: sounds like Crew – site of major rail junction;
24 Pilot is stumped continually being contracted (5)
STEER: ST-EER; stumped=ST (cricket);
26 No more chop chop, poppycock (8)
CLAPTRAP: CLAP,TRAP: chop=old word for CLAP; chop=mouth=TRAP;
29 Our town represented as a dead cliché, for example (7)
WORNOUT: (our town)*;
30 Black stuff left in barbie box (4)
BASH: B-ASH;
31 Unusual ancestor so far wonderfully decent about note (9)
ASCENDENT: AS-(decent)* surrounds N=note;
32 One intake of undergrads ultimately pay attention (4)
YEAR: (pa)Y-EAR;
33 Deserted rescue vessel west of promontory poses a mystery (8)
DARKNESS: D-ARK-NESS; deserted=D (military)

DOWN

1 Bugle-call at GI’s burial/ is piercing (4)
TAPS: two meanings
2 You say this on finding His Eminence outside before show (9, three words)
HERE,WE,ARE: H(ERE-WEAR)E;
3 City understanding what constitutes warning (7, two words)
RIOT,ACT: RIO-TACT;
4 Birds gather moving south as far as poss (4)
AVES: gather=save then move “s” to the end;
5 Disco may pass drug test (8)
DOCIMASY: (disco may)*; pass=become=anagrind
6 Comparatively sparse portion of land fenced off by Bishop (5)
RARER: R(ARE(a))R; RR=Right Reverend;
7 Small pet cut item of tack (8, two words)
STIFF,BIT: S-TIFF-BIT;
8 Moniker for the very tall (?) child who chases up centre-half (4)
TICH: IT reversed; CH; reference game of “It”; CH=centre-half
9 Prompt monarch’s up above PA (8)
REMINDER: ER reversed – MINDER;
14 Flipping pound reduced wealth and shilling stops in the past (9)
SURCEASES: CRUS(h) reversed-EASE-S; pound=crush; wealth=EASE; shilling=S
15 Save blade on plough — accepted and established routine (8, two words)
SOCK,AWAY: SOCK-A-WAY; blade on plough=SOCK;
16 Glass is more readily filled by Chaplain (8)
SCHOONER: S(CH)OONER; measure of sherry;
17 War poet troubled about bit of miracle fruit in LLL (8)
POMWATER: (war poet + m)*; m from m(iracle); an apple, presumably in Love’s Labour’s Lost;
20 Practice head-rhyme, say, with everybody going for repeat (7)
ITERATE: (all)ITERATE;
23 Yard accepted conclusion previously acknowledged (5)
YCOND: Y(CON)D;
25 Predator in the main features in “An Inspector Calls” (4)
ORCA: hidden (inspect)OR-CA(lls);
27 Peer / to give special edge to / exquisite huntswoman? (4)
PINK: three meanings, I think – not sure about “exquisite huntswoman”
28 Shop dished out soups favoured by Asians (4)
PHOS: (shop)*;