Originally Posted by
Tchiowa
The airlines don't unload luggage onto the belt. The airports do. And airport baggage handlers are not going to set aside bags that don't have a priority tag and only pass through ones that do. They are going to load the bags from the bins as fast as they can, first come first served. So it's entirely a matter of loading them properly into the bins at the departure airport.
That depends on the airport/airlines combination. There are actually airlines that still own handling companies.
That being said, JAL and ANA can still make the first class luggage appear first, followed by the business class luggage etc. at Heathrow T3, so the airline influence does exist in some way.