It was for Vanish oxy-clean. The bare essence of the add was this:
"Add one scoop to your washing and it;ll take out the toughest stains on the first clean-or your money back!"
Small print on screen during ad said it only applied to synthetics and wool and leather are specifically excluded.
Watchdog took some football shirts, soacked them for SIX hours as prescribed on the small instructions on the box, then washed normally with a leading brand detergent and the scoop of Vanish. Result. All the stains were still more or less evident.
Vanish replied that it would guarantee grass stains coming out but couldn't guarantee mud stains being removed. Well that's all right then-footballers just have to play on grass but where there is no mud!!!
Basically Vanish got slagged off pretty big time.
Still, it didn't leave any bleach marks in the fabrics

......
......just the stains

Rog