I think the question was why one method is prefered over the other. The balance control mainly controls volumes on each channel except digital delay. Speaker placement controls both volume and time alignment. I'd suggest two simple tests:
1. Switch speaker cables at the amp to see if the favoring side remains.
2. Extream toe in to minimize room interaction. Starting with speaker facing directly at you or in front of you.
1. Switch speaker cables at the amp to see if the favoring side remains.
2. Extream toe in to minimize room interaction. Starting with speaker facing directly at you or in front of you.