No 13029, Tuesday 01 Sep 2020, Lightning

Solution to 26A has been deliberately left unsolved and is to be answered only by a non-regular/novice commenter, with proper annotation. Those who have answered earlier in the week, please give others a chance.

ACROSS
1   Squeeze firm parliamentarian essentially missing break (8) COMPRESS {CO}{MP}{REceSS}
5   Distribute oddly superb tool (6) SPRAWL {SuPeRb}{AWL}
9   Average place to get food cut short a new cheese (8) PARMESAN {PAR}{MESs}{A}{N}

10 Right to flourish leaving society (6) PROPER PROsPER
12 Link with perhaps second electron (5) UNITE {UNIT}{E}
13 Irritability had to be self-controlled (9) TEMPERATE {TEMPER}{ATE}
14 Fiercely vigilant person put on covering (piece of cloth) (6) DRAGON {D{RAG}ON}
16 These may help you see spectacles (7) GLASSES [DD]
19 Leave behind with charge and heat (7) PASSION {PASS}{ION}
21 Gent going around northern Thailand with cloak (6) MANTLE {MA{N}{T}LE}
23 Cover a tax mix-up with machine (9) EXCAVATOR*
25 Choose short, ordinary thread primarily for embroidered loop (5) PICOT {PICk}{O}{Th...d}

26 Ridicule basketball move guarding fadeaway falling short (6) D?B?N? (Addendum - DEBUNK {D{EBb}UNK} - See comments)
27 Pressure damaged core coin (8) COERCION*
28 Left out, to hang loosely by river in jeopardy (6) DANGER {DANGlE}{R}
29 Unrestrained force once veil shattered (8) VIOLENCE*

DOWN
1   Letters from fancy Prussian to country (6) CYPRUS [T]

2   A grid dismantled in planet for festival (5,4) MARDI GRAS {MAR{A+GRID}*S}
3   Chief magistrate, going north, to change direction at Spain (5) REEVE {VEER<=}{E}
4   Simple painting perhaps separating bridge (7) SPARTAN {SP{ART}AN}
6   By mistake, police ran to China (9)  PORCELAIN*
7   This dominant male may come first (5) ALPHA [C&DD]
8   Generosity not enough to cover a royal grand excursion at first (8) LARGESSE {L{A}{R}{G}ESS}{Ex...n}
11 Very satisfied about oral tissues (4) SMUG<=
15 Formal complaint of care given at sea (9) GRIEVANCE*
17 Choice of the French dividing piece (9) SELECTION {SE{LE}CTION}
18 Starting price of loan with identity is very good (8) SPLENDID {SP}{LEND}{ID}
20 Pay attention to short letter (4) NOTE [DD]
21 Injure criminal with one inventor (7) MARCONI {MAR}{CON}{1}

22 Posture in second spell not right (6) STANCE {S}{TrANCE}
24 Taxi not out of small house (5) CABIN {CAB}{IN}
25 Risk for everyone by lake (5) PERIL {PER}{1}{L}

Reference List

Firm = CO, Parliamentarian = MP, New = N, Society = S, Electron = E, Ordinary = O, Left = L, River = R, Spain = E, Royal = R, Grand = G, The in French = LE, Starting Price = SP, Second = S, Rght = R, Lake = L