Mirror adjustment is not a set it and forget it thing. All depends on where you drive. The "NEW" thought about setting them wide is for multilane roads with merging traffic. One a two lane road you want them set the"OLD" way with your rear body lines in sight.
I drive 3 to 400 miles a day on every thing from rural town roads to downtown city traffic to high speed expressways and adjust my mirrors accordingly. Static mirror position was always a compromise before power adjust became common.
I wager that within 15 or 20 years mirrors will be obsolete and replaced three or five position camera system that will give a much more complete picture of your vehicles relationship to others.