If I want to cast Rejuvenation instantly followed by a Swiftmend, it makes me wait for roughly one full second. I'm assuming it's waiting for the Rejuvenation to tick or something. If you hit Swiftmend instead, it highlights your mouse in blue, which means click on the target you want to use it on, because you cannot cast it on your current target (if that makes any sense)
It doesn't seem like a big issue at all to wait that small amount of time, but it really does make a huge difference. We nearly lost the Warsong Gulch when the FC died because of this, but luckily a teammate picked the flag up.
inb4 blizzard doesnt care so they dont post
EDIT: OH!!!! ALSO!!! It says I can get 50 conquest points if I win the battleground (level 86) but it doesn't ever give the conquest :,(