Well, the stat is "Left (club) after last trophy win and have won silverware", so you have to include everyone who left Saints since 1976. Mick Channon winning the League Cup with Norwich in 1985 and Andy Townsend winning it with Villa in 1993 would count, for example. Tim Flowers, Rod Wallace, Alan Shearer, Russell Osman, Neil Ruddock... that's still in the early 90s.