The word `choker’ will get bandied about a lot at the Cricket World Cup.South Africa, regularly among the top contenders entering the biggest event in limited-overs cricket, has never won a knockout match at the World Cup.In a cricket context, choking is a term a previous generation of South African stars got sick of hearing. It’s a cruel tag which AB de Villiers and his current crop of Proteas must overcome if they’re to break one of cricket’s most confounding droughts.Top-ranked Australia and a fast-improving New Zealand are expected to revel in home conditions, while defending champion India, 1996 winner Sri Lanka and 1992 champion Pakistan can never be ruled out of contention.England has experienced some team turmoil in the wake of Kevin Pietersen’s departure and the decision to fire Alastair Cook as captain, but did reach the final at the Melbourne Cricket Ground 23 years ago, when Australia – then the defending champion – didn’t reach the semifinals.But many consider this to be South Africa’s time, if it can avoid the blighted moments that tainted previous campaigns, particularly in 1999 and 2003.In de Villiers, South Africa has one of the most exciting, attacking and well-poised batsmen in the game….