Across:
8 Unfinished (d) pool (‘pond’ without ‘d’ = PON-) fairly (half of) selected (chosen) (half of ‘CHOsen’ = -CHO) (PONCHO) in The Cape? (PONCHO),
9 Characters finishing with 15 across (‘English language’ = LANGUAGE), in a manner of speaking (LANGUAGE),
10 Clare, for one (Clare Island = ISLE), immersed in tennis lesson (immersed in ‘tennIS LEsson’ = ISLE),
11 Bloom’s (blooms = FLOURISHES) in our selfish (our selfish) play (= anagram indicator) (our selfish = FLOURISHES),
12 Throwaway lines (ASIDES) from The Undertones on stage (ASIDES).
14 New (FRESH) tune (AIR) (FRESH AIR) will blow the cobwebs away (FRESH AIR),
15 They share a border with the Scots (ENGLISH) and Irish, for instance? (LANGUAGE) (ENGLISH LANGUAGE) You hear this all the time at Westminster! (ENGLISH LANGUAGE),
18 Cleaned up (CENSORED) dodgy (= anagram indicator) corn seed (corn seed = CENSORED),
20 Promise (PLEDGE) by president (P-) to be brief (r) with accounts (‘ledger’ without ‘r’ = -LEDGE) (PLEDGE),
22 American (A-) can’t (cant = -C-ANT) get over Dracula (-COUNT-) (ACCOUNTANT) is very familiar with The Book of Numbers (ACCOUNTANT),
24 Made a meal of it (FEED) in defiance without Cain (‘defiance’ without ‘Cain’ = defe = FEED),
25 A training method in the grounds (training tree/shrub / ESPALIER) – Leap! Rise! (leap rise) Run! (= anagram indicator) (leap rise = ESPALIER),
26 Left with poor skin (SPOTTY) from opening sweets (opening ‘Sweets’ = S-) and nuts (-POTTY) (SPOTTY).
Down:
1 Half of those in 6 down (half of ‘guesthouse’ = HOUSE-) take direction (south = -S) (HOUSES) from the Dáil and Seanad (HOUSES of the Oireachtas),
2 Peter falls out of peach tree (‘Peter’ falls out of ‘peach tree’ = ache = ACHE) and that’s painful (ACHE),
3 Blur’s (blurs = CONFUSES) scouse (scouse = CO-USES) melody (= anagram indicator) includes introduction to Nutter (introduction to ‘Nutter’ = -N-) that’s loud (forte = -F-) (CONFUSES),
4 Some upsetting (= reversal indicator) taboo slang (some ‘taboO SLAng’ = osla = ALSO) to boot (ALSO),
5 Made up (UNTRUE) with a foreign (a = UN-) tenor (-T-) on French street (French ‘street’ = -RUE) (UNTRUE),
6 Dwelling (-HOUSE) on most of those (s) in 21 down (‘guests’ without ‘s’ = GUEST-) opening (= positional indicator) (GUESTHOUSE) for The Tourists (GUESTHOUSE),
7 Having the same opinion as (AGREEING) top lawyer (Attorney General = AG-) finding drugs (Es = -EE-) hidden by wedding band (R-ING) (AGREEING),
13 Get the munchies here (deli = DEL-I-), going around America (-US-) on (-ON-) a (-A-) Lambrettta, initially (‘Lambretta’ initially = -L) (DELUSIONAL) living the dream (DELUSIONAL),
14 Marched in an army (FILED) with Field (field) Marshal (= anagram indicator) (field = FILED),
16 Lack of a defence (NO EXCUSE) for divorcee (EX-) consumed by criminal (con) falling head over heels (= reversal indicator) (con = NO -C-) at function (-USE) (NO EXCUSE),
17 Turns up (= reversal indicator), American college (Massachusetts Institute of Technology= MIT = -TI-M) admits school (-S-) is accessible to everyone (open = NEPO-) (NEPOTISM) looking after their own family (NEPOTISM),
19 Is this the rank (RANCID) that managed (RAN-) the police department? (-CID) (RANCID),
21 Estimate (guess = GUES-S) covers the first of the (the first of ‘The’ = -T-) (GUESTS) visitors (GUESTS),
23 Broadcasts (AIRS) lie from Israeli (‘lie’ from ‘Israeli’ = srai = AIRS),
24 Current (FLOW) followers dismiss loser (‘followers’ dismiss ‘loser’ = flow = FLOW).