I want to add my 5 cents. Wit doesnt give resist to any debuff and the conclusion on test that dyes changed landrate of fear by 5% is just matter of RNG and statistic error, not the real effect. Also I have tested debuffs on our test server some time ago where i could set men/wit to 99 to make effect bigger and easier to notice. Wit didnt have ANY influence on debuffs on our server, however MEN was for sure giving massive resist to poison, arcane chaos (3rd class debuf) and mabye slow(tyrant cripple) but im not sure about slow since it was several months ago. You are free to log on test server and make the test by yourself, i believe nothing changed since then. I believe its bug because on official con doesnt give resist to stun anymore, so men shouldnt give resist neither in my opinion but i cant find proof for that. I reported it to san0 but he said - no proof. I want to add that CON is still bugged and gives MASSIVE RESIST to stuns and BLEEDS! Ask sayomi, he played SK on oly, every his game i watched, his bleed was insanely resisted by + con build classes.
To sum up
MEN - mana regen, max mp, M def (ppl hit you weaker with nukes when u have more men), the more men, the lower chance to get spell cast canceled by enemy dmg. Also resist to small amount of debufs like poison and arcane chaos (which i believe is bug but cant find official test proof)
WIT - More casting speed, more magic crit chance, more magic accuracy ( higher chance to hit higher lvl targets with nukes), more magic evasion (higher chance to avoid enemy nukes - they nuke you for 0 with cartain chance)