I'm just going to say something on this, from the point of view of someone who has leveled an archer and a warrior separately; it can be annoying from both sides.
For archers, it's annoying having warriors camping for hours in one spot, making it harder to go against decent enemies. The hardest enemies are statted so that it's quite easy for a warrior to stand there attacking them, but for an archer to defeat them by themself, it's much more difficult. For warriors, it's annoying having archers pull enemies away because their small range makes it difficult to run after things and actually hit them.
The static camping style that complements warriors conflicts with the very dynamic style that archers use, so it's natural that there will be some friction between the two classes. Trying to force the other class into one's own style exacerbates that friction, which is what Amun is talking about. Also, most archers don't want to up their vitality and luck because their style renders those stats less useful; it would effectively turn them into warriors, which defeats the point of being an archer.
The cure? Understanding. Don't try to force someone else into your own paradigm. Warriors, don't tell archers to use a sword or camp; archers, try not to pull enemies (I can't really offer more than that). Most warriors don't try to force melee onto archers, so I always try to respect them and stay in the one place, or find a different place to train, but I happen to have decent stats for camping.
Yes, I completely ignored magi, but this post is still relevant to magi versus warriors.
Anyway, good luck reaching level 99 Amun.
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