ACROSS
1 Preferred by gentlemen, dashing fellows working for academic initially (7) 
BLONDES - Preferred by gentlemen (def) from BLADES (dashing fellows) with ON (working) replacing (for) A (academic initially)

5 Crown cover for one of 11's tribe revolting against Tsar regularly (7) 
BIRETTA - Crown cover for one of 11's (hat for clergyman) (def) from BIRET (anagram of TRIBE) TA (Tsar regularly)

9 About to steal pod (5) 
CAROB - pod (def) from CA (about) ROB (to steal)

10 Citroen I'd drive around this way (9) 
DIRECTION - this way (def) from anagram (around) of CITROEN ID

11 Bishop, perhaps, ordained group on island (9) 
CLERGYMAN - Bishop, perhaps (def) from CLERGY (ordained group) on MAN (island)

12 Present time to overdose, indeed (5) 
TODAY - Present (def) from T (time)  to OD (overdose) AY (indeed)

13 Little fish always around lake (5)
ELVER - Little fish (def) from EVER (always) around L (lake)

15 US city like a country or old African territory (9) 
NYASALAND - old African territory (def) from NY (US city) AS (like) A (a) LAND (country)

18 Content for masses to follow princess's discharge (9) 
DISMISSAL - discharge (def) from MISSAL (Content for masses) after ( to follow)  DI'S (princess's)

19 Limit article, say, in letter from Greece (5) 
KAPPA - letter from Greece (def) from homophone (say) of CAP (Limit) A (article)

21 Colour  (5) 
AMBER - Colour (def) from (C)AMBER(S) (naked curves)

23 Attorney general in US state joins Wanderers (9) 
VAGABONDS - Wanderers (def) from V AG A (Attorney general in US state) BONDS (joins)

25 Don't agree to try cooker this month (2,7) 
GO AGAINST - Don't agree to (def) from GO (try) AGA (cooker) INST (this month)

26 Setter caught by vermin coming up step (5) 
STAIR - step (def) from I (Setter) in (caught by) STAR (RATS=vermin) coming up

27 Pushes one to leave this with corrosion inside (7) 
THRUSTS - Pushes (def) from THS (one to leave TH(i)S) containing RUST (with corrosion inside) 

28 Tear around listener's bottom (4,3) 
REAR END - bottom (def) from REND (Tear) around EAR (listener)

DOWN
1 Way for two to get around in tandem (7) 
BICYCLE - Way for two in tandem to get around (def)

2 We are over old city with small sprites (9) 
OURSELVES - We (def) from O (over) UR (old city) with S (small) ELVES (sprites)

3 Fix code for girl coming out on upper gallery initially (5) 
DEBUG - Fix code (def) from DEB (girl coming out) on  UG (upper gallery initially)

4 Mend sites spilling deposits in liquids (9) 
SEDIMENTS - deposits in liquids (def) from anagram (spilling) of MEND SITES

5 Outhouse sheltering old nobleman (5) 
BARON - nobleman (def) from BARN (Outhouse) sheltering O (old)

6 Run on path where Bolt and Hamilton excel (9) 
RACETRACK - where Bolt and Hamilton excel (def) from RACE (Run) on TRACK (path)

7 Heard diet changed around. Right? (5) 
TRIED - Heard (def) from anagram (changed) of DIET around R (Right)

8 Doyen in bits after article irritated (7) 
ANNOYED - irritated (def) from anagram (in bits) of DOYEN after AN (article)

14 Tracks bird on highways (9) 
RAILROADS - Tracks (def) from RAIL (bird) on ROADS (highways)

16 All one thousand on ascending list reveal predator (9) 
ALLIGATOR - predator (def) from ALL IG (All one thousand) on ATOR (ascending list ROTA=ATOR )

17 Programme to finish untitled page for hanger-on? (9) 
APPENDAGE - Hanger-on (def) from APP (programme) END (to finish) (p)AGE (untitled page)

18 Doctor should, with new leader, be current (7) 
DRAUGHT - current (def) from DR (Doctor) AUGHT (aught=ought (should) with new leader) 

20 Made certain idiot landed on posh communist (7) 
ASSURED - Made certain (def) from ASS (idiot) landed on U (posh) RED (communist)

22 Second rate den for old PM (5) 
BLAIR - old PM (def) from B (Second rate) LAIR (den)

23 Sun rising behind empty vehicle exposes goddess (5) 
VENUS - goddess (def) from NUS (Sun rising) behind VE (empty vehicle)

24 City  (5) 
BASRA - City (def) from anagram (attacked) of ARABS