Across
1 Tips goer offered for self-indulgent activities (3,5) EGO TRIPS
5 Model leaves new spiel (6)
9 Report is about royal supporter (7)
10 Concession given to this strange reasoner (7) SOPHIST
11 English pa? (5,4)
12 Best electronic lamp? (5)
13 Thanks — and thanks — to the industrial house (4) TATA
14 Make it big! Nile can be set on fire! (9)
17 Such a vessel must be reliable in the main (9) SEAWORTHY
19 Notion I had advanced to each (4)
23 Discharge from space, say (5)
24 One who goes on a roll on cold surface (3-6)
25 Italian composer goes to court for decision (7) VERDICT
26 Leaving nothing out, mischievous boy gets in walking unevenly (7)
27 Showy marble protected from moisture (6)
28 Support for marriage? (8)
Down
1 Begs the Bengali not to start parties (8)
2 More than satisfy about each kind of shirt (7)
3 Beams from fresh crews? (6)
4 Alertness pigs, infuriated, manifest (9,4)
6 Perfect symbol of Americana? (5,3)
7 Rival IT conglomeration is insignificant (7)
8 The state of Denmark in Hamlet’s days (6)
10 Staggered hits dazed rulers (8,5)
15 Waded to landing ground — it’s more sodden (8)
16 Song from mother on retreat about a girl on a trip (8)
18 Some women have pluck to remove it (7)
20 Recounts where the devil is in? (7)
21 Clergyman to wager about nominal promotion (6)
22 With hands on hips, sailor entertains man with love (6)