I'm not sure you even understand it at all. They didn't change loot mid-tier at all. Right around now would be the point of mid-tier. They literally made the other change a week or two into the raid tier which is completely different than your mid-tier argument. When they made the change that is how they wanted loot to drop based on player feedback so it was "meaningful". The thing is after players experienced it for several weeks they are now realizing their "meaningfulness" isn't as meaningful as they hoped and wish loot dropped more which then drops the meaningfulness down.