Regarding Jeremy Beecham’s thoughts on Roger Waters (Letters, 19 April), I think we can take it as read Waters would not encourage Madonna to support the Assad regime by playing Damascus.

John Warburton

Edinburgh

• You failed to mention the two most important filmed rock concerts (Homecoming review – Beyoncé documentary is a triumphant celebration, 19 April): Monterey Pop and Woodstock. To write about seminal filmed rock gigs without mentioning them is like writing about influential 60s groups without mentioning the Beatles or the Stones.

Jon Ingram

Ilkley, West Yorkshire

• The article about use-by dates (G2, 18 April) reminds me of when I had complimented my wife’s delicious dish. One of the ingredients was fish sauce she’d found at the back of our food store that needed using as it was open, so I took a look at it. It was three years out of date and the label read “when opened, store in the refrigerator and use within four days”! That was 10 years ago and I’ve still not had any after-effects.

Stuart Waterworth

Tavistock, Devon

• Does relentless pacing of the house looking for car keys, glasses, TV remotes etc count towards the “light activity” that prevents brain shrinkage (Every step you take stops the brain from ageing, researchers say, 20 April)?

Harold Mozley

York

• I suppose it was just as well I hadn’t switched off my smartphone before I read your advice (Editorial, 19 April) to switch off my smartphone.

Keith Flett

London

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