I kite jatu ones to noldor when I was at zero relationship.
The Jatu are fast, so make sure you're faster than they are. Usually the Noldor are tad slower, so the Jatu will run away. Just go to them while they are fleeing and then end the conversation without attacking the Jatu. This will cause them to stand still equivalent to 4 times spacebar (just hit spacebar 4 times) and then you will notice for sure that the noldor who's chasing will get closer. Repeat this 5 tot 6 times and they are in battle: join the noldor and you will get 4+ relationships. Or if they are more than 4 and you can easily win, side with Jatu and free the captured Noldor. Break even = when you release 4 Noldor; on the bonus side you will get honour too!
PS: use auto-calculate when choosing the latter option.