I'm aware that I might be foolish to ask this rather simple question but it's stunning me ever since I've finished reading the Goblet of Fire.
In Harry Potter and the Goblet of Fire:
Once or twice, Sirius made a noise as though about to say something, his hand still tight on Harry’s shoulder, but Dumbledore raised his hand to stop him, and Harry was glad of this, because it was easier to keep going now he had started. It was even a relief; he felt almost as though something poisonous were being extracted from him.
The next sentence:
It was costing him every bit of determination he had to keep talking, yet he sensed that once he had finished, he would feel better.
I'm not absolutely sure how to explain to myself why the past perfect here is correct. This is definitely a conditional but a rather strange one to me.
I somehow want to write it as:
- ...yet he sensed that once he would have finished, he would feel better.
- ...yet he sensed that once he would finish, he would feel better.
To me "once he had finished" sounds as if "he did actually finish it once in the past".