As unfortunate as the recent changes of venue have been, it looks like they may have saved lives for both the South African and English cricket teams. Last night the hotel that they might have been staying in was destroyed by a bomb blast.
I'm very happy that the changes were made, as my love of cricket might have been upset today!
It is hard to know how much is enough and with the fact that so many terrorists are willing to lose their lives to achieve their aims, I don't think that there is anything you can really do to stop them.
Yes, these players definitely have enough on their minds without having to worry about security issues. As far as how much is too much, I guess nowadays that depends on how much you value your life and what you are willing to put up with to secure your chances of survival.