Note that the first letter of the answer is ignored in the word play of each clue

Clues:
   A. Fair play snaring colony's first big piece of land (6)
   B. Perform "End of the Line" and "Brazilian Memoirs" along with one some called "About the Little Things" (15)
   C. If I attend, I only ruin discretion (15)
   D. Go too slow in Joplin number perhaps (4)
   E. Thomas is embraced by Bradman (6)
   F. Worked on a mere appellation? (8)
   G. Clear pattern of orthogonal lines (4)
   H. Ferenc Preisach modelled it without a transform... rest is easy! (10)
   I. Overwhelm sister with night out (8)
   J. A flat finish? (5)
   K. Worked in the kitchen with requirement to receive notice (7)
   L. Buttering mash, one's heart's not in it and one drops bits on the ground (9)
   M. Fun to give incorrect data: I'm roughly ten (9)
   N. Roam around with Jean perhaps (5)
   O. Not having one limits food intake for man of dramas (5)
   P. Money handed out in one's confused state (7)
   Q. You finally got creative work with end of jazz-rock (6)
   R. Restating arrangements for someone who's on the list (10)
   S. For jazzy feel, improvise (5)
   T. Dashed to catch the one thing that people dash to catch (5)
   U. Ben's luck rotten... gets free of belt (9)
   V. Russian leader laid out by Russian craft (8)
   W. Note nasty bug (6)
   X. Coming up... 0:54 (5)
   Y. Northern country, or hiker's fantasy (9)
   Z. Bank one obstacle to part of (A) (8)