I’d like to add or explain what I think Tumppi means in his #8:
One often used way to record ADR is to use a technique sometimes called “parroting” or in Swedish “repeat like a monkey” 
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This is where you play the line and the actor repeats the line after hearing it.
This is another use where open ended recording is extremely important.
I think the switching matrix may just be enough to actually handle it already. That is if it has settings for post cycle out point (not post record out this difference is important).
This mode of ADR is a lot more work as it requires more editing, but is often generating a more fluid performance where the actor actually mimics the phrase as such and don’t think about sync during delivery.
This method is often used with actors that are continually late when starting the line but that will try to end the line they hear in the headphones in sync (this means the line will never really fit without some extra stretching surgery). And also with actors who are uncomfortable wearing headphones to the point where the acting is affected.