Both. It depends what result you favour. As the FAQ says towards the end of this section:
3. Where should I position the mic for best results? (click here)
"If you are primarily interesting in getting the best result for just one seat (either because you are the only listener or you are the only listener who really cares about audio fidelity), then place the mic for position 1 at the centre of that seat. If, however, you wish to consider other seats, then place the mic in the centre of the listening area for position 1."
So which does your friend favour? Getting the best result for more than one seat, or the best result for one main seat? The answer to the question decides where the mic goes for position No 1.
Edit: Perhaps I should add this as a specific question under the Mic Placement section. It does come up fairly often...