Personally, I think friendly fire damage should always be full damage, whether in clan or alliance or party or whatever else you can come up with.

You will have to be more careful and coordinate properly to avoid hitting one another :theworst:

Trust me, take any strictly PvE player (no friendly fire at all) and make them do all their PvE with friendly fire at full damage. Their awareness of their thralls/pets, as well as their own fighting skills, will improve drastically (if they don’t give up) because they will have to sneak damage in but avoid hitting their allies (which here are followers).

Pretty sure PvP fighting skills would improve the same way, although probably to a lesser extent.