Thank you to Budmo. Definitions are underlines in the clues.
Across
1. Grazing land beyond river in Yorkshire (7)
PASTURE : PAST(on the further side of/beyond) + URE(river in North Yorkshire, England).
5. Set off bouncy character taking Ritalin, primarily (7)
TRIGGER : TIGGER(fictional character in A.A. Milne’s Winnie-the-Pooh books, who loved bouncing) containing(taking) 1st letter of(…, primarily) “Ritalin”.
Defn: …/cause an event to start.
10. Give out porridge on return (4)
EMIT : Reversal of(… on return) TIME(like “porridge”, an informal term for a prison sentence).
11. Fulmar gets confused in current across the pond (4,6)
GULF STREAM : Anagram of(… confused) FULMAR GETS.
Answer: A strong and swift current in the Atlantic Ocean to be found off the US East Coast, ie. across the pond.
12. Earnest camping like this? (6)
INTENT : [IN TENT](how one goes camping/living temporarily in a tent).
13. Celebrities can’t play snooker for this reason (8)
NOTABLES : [NO TABLES](without these essential requirements for a snooker game, it can’t be played).
14. Map a creek for training frontrunner (9)
PACE MAKER : Anagram of(… for training) MAP A CREEK.
Defn: …, one setting the pace in a race
16. German defeat provides sheen (5)
GLOSS : G(abbrev. for “German” – usage?) + LOSS(defeat in a contest).
17. Some males sexualised in part of eastern England (5)
ESSEX : Hidden in(Some) “males sexualised”.
19. When I am wearing gold in part of Turkey (4,5)
ASIA MINOR : AS(when, as in “when you enter the room …”) + I AM + [IN(wearing/clothed in) OR(gold/the colour yellow in heraldry).
Answer: …, also called Anatolia, the peninsula that makes up the major part of Turkey.
23. Some rugby players argue with impudence, at first (5,3)
FRONT ROW : ROW(to argue/quarrel with) placed after(…, at first) FRONT(impudence/boldness).
Defn: …, collectively, the forwards who form the first row in a scrum.

24. Student has left out source of money (6)
EARNER : “learner”(a student) minus(has … out) “l”(abbrev. for “left”).
Defn: An activity or product that provides income/a ….
26. Rub close-in when partying – this PM liked to (10)
BERLUSCONI : Anagram of(… when partying) RUB CLOSE-IN.
Answer: …, Silvio, former Prime Minister of Italy, who faced allegations of sexual misconduct (when partying).
27. Unpleasant situation of male anger (4)
MIRE : M(abbrev. for “male”) + IRE(anger/rage).
28. Why is husband claiming base is like dairy product? (7)
WHEYISH : [WHY IS + H(abbrev. for “husband”) ] containing(claiming) E(in mathematics, the constant that is the base of the natural logarithm).
Defn: …, in this case, the watery part of milk remaining after the formation of curds.
29. Absolute power of extremely tetchy grandma not good (7)
TYRANNY : 1st and last letters of(extremely) “tetchy” + “granny”(familiar term for one’s grandmother/grandma) minus(not) “g”(abbrev. for “good”).
And such grandmas could be tyrants.
Down
2. Song about blokes in former Soviet state (7)
ARMENIA : ARIA(an operatic song for a solo voice) containing(about) MEN(blokes/chaps).
Answer: A state in the former USSR.
3. Perhaps Mr T wearing hat (5)
TITLE : T contained in(wearing) TILE(slang for a hat).
Defn: An example of which/perhaps is Mr or Mister in full.
4. A cottager wanting company turned up for sporting event (7)
REGATTA : Reversal of(… turned up, in a down clue) [A + “cottager” minus(wanting) “co”(abbrev. for “company”, a commercial organisation)].

6. Change location of temporary relief, heartlessly (6)
RESITE : “respite”(temporary relief/a short period of rest from something difficult or unpleasant) minus its middle letter(heartlessly).
Answer: … or re-site, if you will.
7. Content to snog a ribald Italian revolutionary (9)
GARIBALDI : Hidden in(Content to) “snog a ribald Italian”.
Answer: …, Giuseppe, Italian general, revolutionary and republican.
8. People who dodge adverse exercises (7)
EVADERS : Anagram of(… exercises) ADVERSE.
9. Twit canoodles with action film director (5,8)
CLINT EASTWOOD : Anagram of(… with action) TWIT CANOODLES.
Answer: American film director and actor.
15. Superficially less cross, for ever (9)
ETERNALLY : “externally”(on the outside/superficially) minus(less) “x”(letter representing a cross).
18. High pitched squawk rocks church (7)
SCREECH : SCREE(small loose rocks forming or covering a mountain slope) + CH(abbrev. for “church”).
20. So be it: sex with unknown for convenience (7)
AMENITY : AMEN(“so be it”, an utterance at the end of a prayer or hymn) + IT(a euphemism for “sex”/sexual intercourse) + Y(symbol for an unknown quantity, in mathematics).
Defn: …/a useful feature.
21. Go on too long in swamp (7)
OVERRUN : Double defn: 1st: … in time, past the scheduled end; and 2nd: …/overwhelm.
22. Seizes power in shop (6)
GRASPS : P(symbol for “power”, in physics) contained in(in) GRASS(to betray to the police/shop).
25. Dance in strange bar, mostly (5)
RUMBA : RUM(strange/odd) + 1st 2 letters of(…, mostly) “bar”.
New for me: in 28ac E = base (Euler’s number, a fundamental mathematical constant approx 2.71828); FRONT ROW rugby players.
I only know G=German from cryptics and have never seen it used elsewhere.
Thanks Budmo and scchua
I thought some of this was rather hard for a Quiptic. I used an anagram solver for BERLUSCONI, who wouldn’t have sprung to mind as PM. LOI was WHEYISH, which I found difficult to believe was actually a word.
Some nice clues, though. TITLE and ASIA MINOR favourites.
I thought 25 needed an elegant variation rather than having “bar” in the clue. Otherwise all was good. Particularly liked 7d, one of my favourite historic Italians (but can you still get his biscuits anywhere?)
I couldn’t account for the ‘e’ in WHEYISH (I doubted the word too but it definitely exists) and I’ve never heard of ‘tile’ as slang for hat. I got 15d, ETERNALLY, from the definition and crossers because I didn’t spot the connection between ‘superficially’ and ‘externally’. Otherwise the answers went in remarkably smoothly. Very nice on a rainy Sunday morning.
Good quiptic and in my view not one of the harder ones. Particularly liked the well hidden Garibaldi and the less cross device in eternally Thanks to Budmo and blogger.
There are quite a few comments on the site itself about the level of difficulty, whereas for me this felt very well-pitched and navigable. The converse is often true, though. Anyway, I found it most enjoyable.
I found it pretty straightforward as well. Like someone above I have never heard of tile as slang for hat but G is the usual abbreviation for German in crosswords. Odd, as you’d think it would be D, but there you go.
Whij@3
You can get the biscuits in Tesco (other supermarkets are available). There are also plenty of recipes online. But I’m afraid they will always be squashed fly biscuits to me.
I found this one very straightforward. Raised an eyebrow at “wheyish”, but yes, it’s a word. Thanks scchua and Budmo
This was a paradox. I sailed through without leaving the app, but all the way along there were little things I thought were tricky for a Quiptic. I’m not surprised it has split opinion. Very much in my wheelhouse though and I enjoyed it.
PS. WHEYISH, can’t see me using that one!
Thanks Budmo and scchua
Tile for hat. https://www.youtube.com/watch?v=aR2UtzqZ7Yk