Derrick Somerset Macnutt

Derrick Somerset Macnutt (1902–1971) was a British crossword compiler who provided crosswords for "The Observer" newspaper under the pseudonym Ximenes. His main oeuvre was blocked-grid and "specialty" puzzles. Even though he only provided conventional blocked puzzles once a week for the "Observer" Everyman series for about two years his strong views on clueing, expressed in his 1966 book, have been a source of debate in the cryptic crossword world ever since.
Career.
Macnutt was born at Eastbourne in Sussex and was educated at Marlborough College before achieving a Double First in classics at Jesus College, Cambridge. Between 1928 and 1963 he held the position of Head of Classics at Christ's Hospital near Horsham, West Sussex, as well as being a housemaster.
In 1939 he took over the position of crossword compiler for "The Observer" on the death of Edward Powys Mathers, who had written under the name of "Torquemada". Macnutt selected the name Ximenes after Francisco Jiménez de Cisneros, one of Torquemada's successors as Grand Inquisitor of the Spanish Inquisition. He pronounced 'Ximenes' in an Anglicised fashion, .
His crossword style was initially in imitation of Torquemada, but was soon influenced by the inventive puzzles of Alistair Ferguson Ritchie who wrote as Afrit in "The Listener".
Macnutt died in 1971, and puzzle 1200, his final crossword to be published, appeared in 1972. He was succeeded by Jonathan Crowther, who writes under the name Azed.
From 1943, he was also a contributor to "The Listener", writing crosswords under the pseudonym Tesremos – his middle name spelled backwards.
Influence.
As Ximenes, Macnutt's puzzles gained an enthusiastic following. His many fans organised dinners on the occasion of his puzzles number 100, 250, 500, 750 and 1000, with the 1968 dinner hosting nearly 400 solvers. His followers, known as Ximeneans, often sported a specially designed black tie covered in small white crosses.
Well-known Ximeneans include Stephen Sondheim, P. G. Wodehouse, and Leonard Bernstein. Colin Dexter, author of the "Inspector Morse" books, named his most famous characters after two prize-winning Ximeneans, Sir Jeremy Morse and Mrs D. W. Lewis, and he named Morse's old Inspector Macnutt. In Rex Stout's "Might as Well Be Dead" (1956), detective Nero Wolfe is said to be working on a puzzle by Ximenes. 
In his 1966 book, "Ximenes on the Art of the Crossword" (reissued 2001), he laid down rules that he claimed should be present in all good crosswords. These are now known as the "Ximenean principles". They include using a symmetric grid, and the specification of maximum and minimum numbers of "unches" (unchecked letters i.e. ones that only appear in one word in the grid) for a given length of answer. More importantly, he insisted that all clues must be scrupulously fair via rules that were summed up by his successor, Azed, as:
He made a number of innovations in crossword setting such as the special clue/puzzle types 'Misprints' and 'Right and Left'.