In Legion, if you get an item from a dungeon or raid with personal loot that isn't an upgrade for you (lower or equal item level for that slot), you can trade it to another eligible player.Now that is different from having a duplicate item in your bag! This is a great change and reduces waste (and also having to keep rubbish loot in your bag), and also will enable raid teams to gear up faster as those who are "lucky" can at least pass some of that luck to others who may need it.
Someone in my guild suggested that it was possible to roll on bosses that had high demand items (like trinkets or other gear) so that if everyone used a coin, then there would be more of that demand item to be created and passed around. Of course, that would require people to HAVE lots of coins in the first place, and I'm not sure if coined loot can be traded. Is that loot considered personal loot? If it is, then it would be nice if you could help your raid members out.
We have been trialling around with the AMR Team optimiser, and I have quite liked it, but with these changes to personal loot, we may use it for some time yet.
I'm now even more excited for Legion than I was before! From my count we won't have the raider overload we had in WoD, so we're looking probably max 25 heroic raiders (more likely closer to 20), and perhaps 15 normal/casual raiders (which of course the raid may fill with heroic raiders chasing loot) so we will have plenty of people to play with in Legion.