Across:
   1. Mother aimed to forgo AA, but acted quietly  (5)
   4. Ducks fruit (9)
   9. Nice Scott involved with study of global developments (9)
  10. Singer alternatively follows number (5)
  11. Most peculiar: pies amongst what was stolen (8)
  12. Go ape about sweetheart at greatest distance away (6)
  15. Clever notice: "Lost Pet!" (5)
  17. Ronald McDonald's heart ripped out by lentil dish being much appreciated by children (5 4)
  18. see 18dn
  19. She left, oddly, where people don't like being left (5)
  21. see 18dn
  22. Being very particular, captained without a mishap (8)
  25. 51-50 ... a close lead to purple (5)
  27. With nothing lost brewing tea, Spooner invented new language (9)
  28. Kitchen equipment changes to beget rage (9)
  29. Unkind remark not available with pen (5)
Down:
   1. Work of 17 - may be waltzing in the 6? (7)
   2. Odd cosmic drone for a period at one megahertz (11)
   3. Clothing seen in arid hot India (5)
   4. I'm "sane" - a term contrived for "going with the flow"? (10)
   5. Essentially, honestly, home (4)
   6. Foolish, so mostly 22ac at greatest distance away (9)
   7. Dinner provided here (3)
   8. Bizarre - a ruler's nightmare (7)
  13. Markers - the most serious ones! (11)
  14. Specialist role on estate - he may have monopoly? (10)
  16. Hot coat he crafted ... it could be a response to cold (9)
  18,21ac,18ac,20. Prince, with sweet production facility, made popular hit of 17 (7 3 3 9 7)
  20. see 18dn
  23. Frying pan or other kitchen equipment (5)
  24. see 26
  26,24. Ottoman local leader greets vagrant (3 4)