Across:
8 Messed about (PLAYED) providing parking (P-) place (-LAY-) for writer (-ED) (PLAYED),
9 Monk used (monk used) mixture (= anagram indicator) (monk used = UNSMOKED) that hasn’t been cured (UNSMOKED),
10 Make a deep impression (ETCH) with sample of gourmet cheese (sample of ‘gourmET CHeese’ = ETCH),
11 Has an effect on (INFLUENCES) fine uncle’s (fine uncles) adaptation (= anagram indicator) (fine uncles = INFLUENCES),
12 For the consumers it’s a hot addition (CHILLI) to Catholic (C-) hospital (-H-) sick (-ILL) unit (-I) (CHILLI),
14 Maids lie (maids lie) badly (= anagram indicator) (maids lie = IDEALISM) out of unrealistic pursuit of perfection (IDEALISM),
15 They’re likely to defend the culprits (CRIMINAL LAWYERS) and barman (LAWYER-) in The Young Offenders, for instance (CRIMINAL -S) (CRIMINAL LAWYERS),
18 Sidney (S-ID) admits pressure (-P-) to extend credit (-LEND-) (SPLENDID) outstanding (SPLENDID),
20 Has a reputation for exposing (NUDISM) type of philosophy that’s not in favour of cover-up (NUDISM),
22 Time (T-) for a (-A-) joint (-J-) in Minister’s residence? (rectory = -R-ECTORY) (TRAJECTORY) Of course! (course = TRAJECTORY),
24 Noel Coward dismissed oracle (‘Noel Coward’ dismissed ‘oracle’ = nowd = DOWN) in Ulster (DOWN),
25 It’s the Pope’s decision (RESCRIPT) a fair amount of (half of) the study (read) (half of ‘REad’ = RE-) is read by those at the abbey (is read by those at The Abbey Theatre = -SCRIPT) (RESCRIPT),
26 Recording (NOTING) away (not in = NOTIN-) game from the start (‘Game’ from the start = -G) (NOTING).
Down:
1 Some of the chicks (CLUTCH) with Cult (cult = -LUTC-) playing (= anagram indicator) (cult = -LUTC-) in church (C-H) (CLUTCH),
2 Bit of gloomy thought (bit of ‘glooMY THought’ = MYTH) in allegory (MYTH),
3 It’s got nothing to do with taking away (ADDITION) one of the tables (ADDITION tables),
4 Lay off fall guy (‘lay’ off ‘fall guy’ = flgu = GULF) in abyss (GULF),
5 Russell (A-E) admits small (-S-), mild rebuke (-TUT-) (ASTUTE) is ingenious (ASTUTE),
6 Made light of (DOWNPLAYED) 24 across (‘down’ = DOWN-) and 8 across (‘played’ = -PLAYED) (DOWNPLAYED),
7 Writing (from the 3 Rs = R-) to English (-E-) landlord (-LEASER) (RELEASER) opens the floodgates perhaps (RELEASER),
13 Would (would) say (= homophone indicator) (‘would’ = ‘wood’ = LUMBER-) one of those in the pack (one of those in a pack of cards = JACK) (LUMBERJACK) is bound to take Holly out (LUMBERJACK),
14 Did nothing (IDLED) in games from Middle Ages (‘games’ from ‘Middle Ages’ = iddle = IDLED),
16 Tweeted (REPORTED) from Dunmore East, for one (-PORT-), surrounded by grass (RE-ED) (REPORTED),
17 Woman (ANN-) loses the head (t) toying (toying) (‘toying”’ without ‘t’ = -OYING) (ANNOYING) with irritating type (ANNOYING),
19 It’s a sham (DECEIT) coming back (= reverse all indicator), unable to move (tied = D-EIT) outside Clare (CE = -EC-) (DECEIT),
21 Glaswegian misses gala (‘Glaswegian’ misses ‘gala’ = swegin = SEWING) using a needle (SEWING),
23 Promise (OATH) of a hot (a hot) dish (= anagram indicator) (a hot = OATH),
24 Cameron isn’t part of documentary (‘Cameron’ isn’t part of ‘documentary’ = duty = DUTY) out of loyalty (DUTY).