well, this is a good example of the dangers of dropping to the lower level of the opposition; taken out of context, the images in the slides have a counter-productive effect on the presentation. You just always have to hold higher standards, or get dragged into the mud.
To go an entire World Cup without conceding a goal is unprecedented, and I would expect the probabilities to reflect this. I seems that the probabilities are calculated independently.
Nope, from the wp article: "The bus factor is the total number of key developers who would need to be incapacitated [...] to send the project into such disarray that it would not be able to proceed"