Can you elaborate more on this? What level of mobs are you attacking?

I thought that even if a high level kills a green mob originally tagged by a level 1, the xp the level 1 can get is capped. You're saying that if the level 1 is in a group with a level 70, but an ungrouped 70 actually gets the kill (say of a level 65 mob), the level 1 will get full xp? Like 1000 per mob or whatever?