I have, and assuming your predecessor doesn't mind, you still get enough useful answers to make it worth it a lot of the time. Especially if you manage to get

I have, and assuming your predecessor doesn't mind, you still get enough useful answers to make it worth it a lot of the time. Especially if you manage to get to just chatting about the project - at some point they'll almost certainly go "oh! while I remember," followed by the answer to a question you didn't realise you should've asked. The value is often in the commiseration rather than the interrogation, basically.