No 12161, Monday 13 Nov 2017, Afterdark

ACROSS
9   Son's mischievous and mean (7) SELFISH {S}{ELFISH}
10 Idea is to introduce power/current in bulb (7) OPINION {O{P}{I}NION}
11 Helps to cook beans adding a bit of lemon and elaichi (7) ENABLES {ENAB{Le..n}{El...i}S*}
12 Forget gym; develop grey matter at ashram (7) RETREAT {gREy+mATTER}*
13 Stopped? No, by mistake put off (9) POSTPONED*
15 Reading mail on police officer's new rule (5) REIGN {R}{E}{IG}{N}
16 Money is returned in store (7) DEPOSIT {DEPO{IS<=}T}
19 Revolutionary participating in violent stir against the wealthiest (7) RICHEST {RI{CHE}ST*}
20 Cook oats properly by following recipe (5) ROAST {R}{OATS}*
21 Somehow locates and takes a rupee in lift (9) ESCALATOR {ESCAL{A}TO*}{R}
25 Original inhabitants were innocent to welcome traders first, with haste essentially (7) NATIVES {NA{Tr...s}IVE}{haSte}
26 Desert-dwellers travelling ice-bound get cold (7) BEDOUIN {IcEBOUND}*
28 Clearing prelims is easier (7) SIMPLER*
29 Heard it’s easy to maintain margin at a corner in excel (7) ECLIPSE {LIPS} in {ECE}(~easy) (Addendum - (~easy){EC}{LIP}{SE} - See comments)

DOWN
1   Resting a top spinner? People will agitate, strike work (6) ASLEEP {A}{Sp...r}{PEopLE}*
2   Every time a law is broken, money wins finally (6) ALWAYS {A}{LAW*}{m..eY}{winS}
3   Wish wife imbibed life lessons for starters (4) WILL Acrostic
4   Select children based on one's drive (6) CHOSEN {CH}{ONES}*
5   Company car I drove on the edge, near gate on passage (8) CORRIDOR {CO}{RR}{I}{Dr..e}{OR}
6   Old IIT scholar ill-treated (10) HISTORICAL*
7   Knot in story's rational too (8) LIKEWISE {LI{K}E}{WISE}
8   Instruction changed after our release by impulse (8) INSTINCT INSTruCTIoN*
14 Certainly, assumption I have logically has no substance (10) POSITIVELY {POSIT}{I'VE}{Lo...lY}
16 Date on a boat near cape at night (8) DARKNESS {D}{ARK}{NESS}
17 Chargeback given after show or break (8) PLAYTIME {PLAY}{EMIT<=}
18 Money plant cut as urea is in short supply (8) TREASURE {TREe}{AS}{UREa}
22 Guys found in taxi fleets regularly (6) CABLES {CAB}{fLeEtS}
23 Defeats sincere (almost) politician in polls at last (6) TRUMPS {TRUe}{MP}{pollS}
24 Leased corner room and entered doling money (6) RENTED {Room}{ENTEreD}
27 Toy is approximately 67 cents in USA (4) DOLL {DOLLar} 67 cents = 2/3 dollar

GRID