i have no issues with high levels party syncing into low level BGs, but their abilities should be inactive or capped to the level of BGs they enter
i was just in a 10-19 BG there was a ret pal using abilities that are not available to other ret pals of the bracket. i did a armory of the player who was a 80. this player hit my player with wake of ashes, divine toll, the list goes on and on. this 80 was moving at immense speed compared what is normally seen in a 10-19 leveling BG, was 1-2 wipe players with ease, worst part there were two other 80s a DH / mage, with abilities above what a true 10-19 of the classes would have