I keep in mind temperature change AND PH change when moving fish. I move fish a lot. not only when i buy them but when i am moving them to different growout tanks. Outside of the pond scenario, i can watch the fish behavior for days after they are introduced in my fish tanks. I dont think a lot of people realize this but poor transport conditions (low DO, high ammonia, large temp swing, large ph swings) dont always cause immediate fish deaths. Most transport fish deaths occur 24-48 hours later and a person stocking a pond would likely never know most/all of their fish are dead.
The trip from shreveport was who knows how long in a truck then 3 hours in air bags with oxygen. i had 1 death (out of ~150) and i think it was trauma from getting pinched in the corner of the bag when i put the bag in the ice chest.
I also put the bags in an ice chest and if i cant shut the lid (usually cant) i throw a heavy blanket over it to keep it dark (fish less active) and to keep the sun from changing the water temperature.
This is benefit of taking the trip to overtons, he will salt and put the bags in boxes. The boxes cost a little extra but they are worth it for how much they help with transport stress
brian