Times 25721 - if I had a million 22s

Solving time : 20:32 on the club timer with more than half of it unraveling that bottom left hand side, mostly held up by the honking great cryptic definition of a word I'd never heard of at 22 across. At the finish I had to go check and it is in both Collins and Chambers, but to me it's a word too obscure to clue using a cryptic definition.

I was also caught out by one of the older tricks in the book at 15 down and was kicking myself there. At the end of things I was second on the leaderboard, so I suspect I am not going to be the only one pulled in to the tricks of the setter.

Away we go...

Across
1	REPAST: PA in REST
4	WREATHES: (WEATHERS)*
10	AMARYLLIS: A MARY, then SILL reversed
11	TON(fashion),ER(head lady, the Queen)
12	LOO(ked): or possibly LOO(med)
13	ON THE SQUARE: double definition, which reminded me of "Monty Python's The Meaning Of Life"
14	TIPCAT: 1,PC in T(h)AT. Apparently this doesn't involve upending an actual mouser
16	TEACH-IN: EACH in TIN
19	ALMANAC: MAN(chap) in AL(gangster),AC(bill)
20	BUYOUT: YOU in BUT
22	PETRODOLLAR: cryptic definition
25	E,GO: GO was very popular amongst students at Melbourne Uni in the late 80s
26	GENOA: double definition (it's also a type of salami)
27	(w)INTE(r),GRAND - mathematical function
28	ROAD TEST: (TREATS,DO)*
29	INFEST: sounds like INN, then FEAST without the A(vailable)
Down
1	REALLY: E in RALLY - as an expression of sarcasm
2	PLATONISM: TO in PLAN, then IS, M(etaphysics)
3	SAY-SO: hidden
5	RESPECT,ABILITY
6	ANTIQUARY: A,(QUAINT)*,RY
7	HENNA: HEN(layer, of eggs), over N(atural),A(ttractiveness)
8	SERGE,ANT
9	PLATE TECTONICS: 1 in (LATEST,CONCEPT)*
15	CONSONANT: since I is not a consonant, it's a vowel
17	HOUSEMATE: (MOUSE)* in HATE
18	RAMPAGER: RAGER grabbing A,MP
21	HOLD IT: OLD in HIT
23	TANKA: sounds like TANKER
24	REGAN: take the A out of REAGAN for Lear's daughter