When this was discussed more than two years ago (yes, time flies), I read on an official website that only 30% of all suicide attempts on the London Underground rails are successful - notably including those involving trains. That Polish tourist seems to have been of remarkable marksmanship. Not all survivors are likely to be at excellent health, though.

Anyway, KK's fictional Casey seems to have been among those 30%, half deliberately, half by accident / drunkenness / carelessness.