Did you watch "Lewis" this evening?

As befits the topic, the obvious link tells you nothing!

But did you spot the threshold concept? [Yes, "how sad can you get?" notwithstanding..] The Haydn Gwynne character, maths lecturer, sets a probability problem for her class early in the story. It is about darts, and the odds of player A or player B getting to zero first...

Part of the information she supplies concerns the previous form of both players. I think that is totally irrelevant. The probabilities of the present situation are quite independent of previous success; this is counter-intuitive, hence troublesome knowledge, and possibly a threshold concept.

But is this the case? The probability of success on the basis of previous form is (presumably) a measure of skill, since darts is not a random game...

I have no idea of the answer, of course. I don't even know if there is one.