But I wouldn't want to argue the toss to try and get a knife with a 5cm blade on board, and if it's a Swiss Army knife they will get you on the corkscrew instead.
Amazing.
It
states:
Blades over 6cm. That means 5cm is OK
It does
not state you can't bring a corkscrew on board.
Common sense has to prevail. If it's a small swiss army penknife with the usual attachments, then according to the rules, it is not a problem. If on the other hand, you try to board with the mother of all corkscrews or five 5cm throwing knives then expect to be stopped.
Having said all that, I think this thread is just trying to make trouble for the sake of it. It's been done to death elsewhere.