Solution to 15A has been deliberately left unsolved and is to be answered by a non-regular/novice commenter, with proper annotation. Those who have answered earlier in the week, please give others a chance.
Open for anyone to answer, if not solved by 1 PM.
ACROSS
8 Unveil jersey for professional horse rider (10) SHOWJUMPER {SHOW}{JUMPER}
9 Fail to cut and fall (4) FLOP {F}{LOP}
10 Most splendid, model kind of hair damage (5,3) SPLIT END {SPLENDId+T}*
11 Lifeless and completely overwhelmed by depression after retiring (6) PALLID {ALL} in {DIP<=}
12 A strong hand stretched to gratify (4,4) LONG SUIT {LONG}{SUIT}
15 Solicitor spending time on good turns occasionally to excel (6) O?T?U? (Addendum - OUTGUN {tOUT}{G}{tUrNs} - See comments)
16 Stop or cap it subtly for making chip (6,5) POTATO CRISP*
22 Kid involved in urban terrorism (6) BANTER [T]
23 Genetics deciphered it? Yes, internally! (8) HEREDITY [T]
26 Make something neat! It's possibly stupidity! (4,2) TIDY UP {TIDY+UP+ITS}*=STUPIDITY
27 Use nice grand solution for upgrading race (8) EUGENICS {USE+NICE+G}*
28 India's first scam superstar (4) ICON {In..a}{CON}
29 Mirth rating possibly for Italian Vermouth (10) EVALUATION {EVALUATION+MIRTH}* = ITALIAN VERMOUTH
DOWN
2 Absconding fellow grovelling for shelter (6) AWNING fAWNING
3 Lover welcomes your company (6) BUREAU {B{UR}EAU}
4 Personal article in Europe Daily (2-2) OP-ED [T]
6 Inspiration for a poet - a loud set from America (8) AFFLATUS {A}{F}{FLAT}{US}
7 Firm and devoted liberal (7) COPIOUS {CO}{PIOUS}
13 Regularly sweat to get established (3) SET {SwEaT]
14 Canine is also half of this! (5) TOOTH {TOO}{THis}
17 Cold, dishonest and isolated (8) OUTLYING {OUT}{LYING}
18 See rapid changes in jet's pace (8) AIRSPEED*
19 Rage, without feminine passion (3) IRE fIRE
24 Fix our suffering (6) RIGOUR {RIG}{OUR}
25 Mark of French-English School on head (6) DENOTE {DE}{ETON<=}
27 Kind of lean style (4) ELAN*
Reference List
Fail = F, Model = T, Time = T, Good = G, Grand = G, Small = S, Fellow = F, Loud = F, Firm = CO, Feminine = F, Of in French = DE
