There seem to be four RVR objectives per faction pairing per tier. Each of the sergeant heroes (or champions for tier 1) offer a special 30 minute buff: either increase healing taken, or increase armor, etc. One of the buffs in particular though buffs your crafting skill by 10 points.
Now, I don't know about you, but I like to do crafting and I've found this buff to be extremely helpful. The reason for this is that those last 10 points are a real bitch to get when you are using the appropriate level mats. If, however, you can run and get this buff you can score some quick points by using the next level mats (for example at skill level 40, with the buff you can start using the skill level 50 items.) This is extremely helpful in the case of cultivating since in some cases the buff will temporarily unlock an extra cultivation plot (if you happen to be just short of that skill-wise) which allows you to raise your skill even faster!
Now, I don't know about you, but I like to do crafting and I've found this buff to be extremely helpful. The reason for this is that those last 10 points are a real bitch to get when you are using the appropriate level mats. If, however, you can run and get this buff you can score some quick points by using the next level mats (for example at skill level 40, with the buff you can start using the skill level 50 items.) This is extremely helpful in the case of cultivating since in some cases the buff will temporarily unlock an extra cultivation plot (if you happen to be just short of that skill-wise) which allows you to raise your skill even faster!