Explanations
Across:
1. Straightforward is seen to be BLACK AND WHITE and not grey,
10. AS THE CROW FLIES - ELECTOR = SAWFISH which is a swimmer (Deletion clue),
11. The sound of around (BALL) and Q (CUE), used to take the shot,
12. 50 (L) strong cockney (ARD) and LARD is FAT,
13. Mixed indicates anagram of Fibre and brief is short,
15. Twisted indicates anagram of ROT and Century (C) and a TORC is twisted metal,
17. A means to an END and END is at last,
19. A CADDIE helps with the tea (TEE) in golf,
21. RETYPE crossword,
23. Waits or WEIGHTS involving six (VI), by the sound of it,
25. Sounds like pleas in court (PLEASE) and PLEASE is a humble request,
27. Close (SEAL) without 50 (L) is SEA to sail in,
29. Encores - 20 down (ENS) and the CORE is the centre,
30. HARSH is rough and unpleasant,
31. A HERB is used in cooking and medicine,
34. ALUMINA is a form of Aluminium,
35. The first T is higher than the second, relating to food (OF COURSE),
36. To BLACKGUARD is to abuse verbally and can. Dark and protector are synonyms.
Down:
2. Behold (LO) + WERE + 50(D) and lowered is to put down,
3. Able (ABEL) murdered his brother CAIN,
4. Father has to turn (AD) + HERE, to carry out the plan,
5. Fish was back (DOC) with a week (k) +Edward (ED),
6. Mess indicates anagram of EH and ED,
7. Comfortable in slang (COSY) and T by the sound of it is (TEA),
8. Milton Described it is AS BLACK AS COAL in Paradise Lost,
14. Anagram of HERNIA + 50 (L),
16. A+ X (IO) +51(LI), which is a sauce,
18. Similar to black this is MERLE which is a coat,
20. MENSA - MA = ENS and ENS is a military banner,
21. Or tea (RT) is after REP and a REP helps you,
24. Mess indicates anagram of ritual and five (V),
26. AVESTAN is the Old Iranian language or tongue,
27. Tie land or sounds like (THAILAND) and bought with a unit of SATANG which is a unit of Thai currency,
28. ASTHMA is bad regarding airways,
32. 30 is the atomic number for zinc. The last letter (Z) + in+ sea (C),
33. A gee (A G) and Edward follows it (ED) and to cure is to age.