Oh no not another free will thread.

[GrandizerII]

No, see my previous response. Full knowledge of a future choice C does not necessarily determine the choice, but such knowledge does indicate it isn't a choice made freely in the libertarian sense.

Freely in libertarian just says that it's a choice, not causal determinism.

Under libertarian free will, it is possible that nothing determines the choice one makes. Logically incoherent, but that's the free will the typical theist believes in.

Prior to receiving the tape from the future, Bob can't know what Larry is going to choose, which rules out causal determinism, no?

Not necessarily. The only way to rule out causal determinism is to say that choices can be made randomly, which is not what you're assuming here. Larry still chose what he chose for a reason. And Bob simply observes that choice in advance.