Under the heading "The great escape" the following letter, from one of the UK's foremost writers and critics, appeared in today's Daily Telegraph. Sir, It was with a great sense of relief that I read about the Royal Opera's cancellation of a schools matinee of Harrison Birtwistle's Gawain (Jan. 19). Hundreds of children have had a narrow escape. If they had been forced to sit through that dreadful piece, they would almost certainly have been put off the art of opera for life. Charles Osborne London SE1 I must confess to agreeing with him totally. How can one possibly start children off in life at quite the wrong end of the spectrum? John G. Deacon Home page: www.ctv.es/USERS/j.deacon