My musings last month about crossword conventions that should be considered past their sell-by date (such as 'actor' indicating TREE, because Sir Herbert Beerbohm Tree was a leading actor and theatre manager until he was sadly gathered in 1917 at the age of 64) produced a lively email bag. There was a pretty general view that CHE is still acceptable, because of his continuing popularity on T-shirts and because of recent films, such as the 2004 Motorcycle Diaries. And so is "chairman" for MAO, because the results of his great achievements and his monumental mistakes continue to affect China and the rest of the world. More surprisingly, perhaps, was the considerable support for a view that crossword conventions with long-forgotten origins should be preserved, because it was a good thing for younger solvers to become aware of them and enjoy them as part of a slightly arcane world they were entering.

To be honest, I don't feel entirely comfortable with this view and so will maintain the ban on TREE but be more flexible about CHE and MAO. Also unaffected for the time being is the convention that phrases in clues, such as "on board ship", indicate that the solution has an "S" at the beginning and an "S" at the end. This is because "SS" in front of a vessel's name meant that it was a steamship, though none of these has been seen on the high seas for some time. The most delightful comment came from Catherine H, a lady in her late 70s who admitted that she got a bit lost with modern music references in clues but argued strongly in favour of TREE preservation. However, she concluded, in crosswords as in other things it is not possible to "please the young and appease the old". (I shall add this neat phrase to my stock of replies for use with disgruntled correspondents.)

When the French group Hachette took over the venerable Scottish publisher Chambers Harrup and shut its Edinburgh offices, moving the various parts of the operation to London and Paris in 2009, there was concern that this might be the beginning of the end for Chambers' traditional interest in crosswords. It is now clear that this was quite unjustified, for in the last four years there has been a steady stream of new and updated publications aimed at crossword fanatics. A third edition of the Chambers Crossword Dictionary (first published in 2000) appeared in hardback in 2011 and in paperback in 2012. Lots of Chambers mobile apps, useful to crossword solvers, are now on the market. Don Manley is working on a fifth edition of his Chambers Crossword Manual, scheduled for the second half of next year. And a new publication, the Chambers Complete Crossword Companion (hardback, £39.99), has just been published. It is a handsome and substantial volume in the same large format as the main Chambers Dictionary. It includes some of the material in the Crossword Manual, an interesting history of the development of the cryptic crossword and an enhanced version of the useful material and lists in the Crossword Dictionary. It is described as "a Rolls-Royce option for serious crossword fans" and the claim is justified.

The March Genius (No 129 by Puck) produced 30 correct entries on the first day and 273 in total by the deadline. Following a now regular pattern, Dave H was first in, followed by Tony of Demon. The first in from overseas was MJS from New Zealand. Congratulations to Sheila Green from Powys, Wales, who is the winner of the March Genius puzzle.

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