There is a further point about the most recent manifestation of Wallop Mrs Cox, the splendid Birmingham-based musical, which I didn't have space to mention last week.

I am sure that writer Euan Rose, who saw the Northfield Musical Theatre Company production on its second night at the Crescent Theatre, must have been distinctly intrigued, to say the least, by the scene involving American military police and the arrest of a GI, who was told that his alleged misdemeanour was "a hanging offence."

Apart from the summary justice dispensed by lynch mobs in all the best cowboy movies, I believe that judicial hanging is quite hard to find in the United States.

What the Euan Rose script says is "a burning offence" - because the role of the soldier has been written to be played by a black man and this is an incident designed to remind the audience of the mindless terror that was inflicted on black people by members of the Ku Klux Klan on the other side of the Atlantic.

The classic case of interference with the script - which is done, incidentally, at considerable risk of sanctions being applied by rightsholders to any company caught at it - is to be found in Guys and Dolls. It has happened at practically every production I have seen and it came as a surprise when I found that it is not actually in the script at all.

It is at the end of the scene when Nathan Detroit is in a telephone kiosk, trying in vain to find a venue for his travelling craps game. He says something rude to the uncooperative citizen at the other end and slams down the phone - after which, the disembodied voice replies in a thick Bowery tone, "And you, too!"

It always brings the house down - but it should not be there at all.

Having said that, I am quite certain that it is something the authors would have been delighted to have thought of in the first place, because it's a delightful moment.

And those sanctions? There is a tale that must send a shiver through the spine of any company that decides to take liberties with a script. A rightsholder ' s representative, realising that the production was exceeding its rights, rose from his seat and stopped the show - for the rest of the run.

And no, I don't have corroborative details - but it is a well known story and even if it isn't true, it is surely a brave or foolhardy company that decides to risk it, because I am assured that it is perfectly possible that it could happen.