Warriors already have to get GLD to 15 just to unlock their soul crystal. If they are unwilling to push it 7 more levels to 22 for a REQUIRED endgame skill, they fully deserve every bit of grief and kicking they get until they get off their butts and do it. There is absolutely no reason whatsoever for people to get to max level on one job, and not have the required cross class skills for that job. With the exception of Mantra (PUG 42), the highest you have to take any class for a skill is 34. Swiftcast is only level 26, Healers who can't manage that much of THM make me suspect of their ability to be a healer anyway.

Any lower level job receives a massive experience boost: 100% up to 50, and 50% 50+, so it's not like it's going to take days. At most a couple hours.