I actually agree in that it's a bit ambiguous simply because of the additional information clause.
Dicussion of "mods", hacks, cheats, or other exploits for Mabinogi, Vindictus, or other Nexon games is permitted, however, you may not request or post additional information concerning exploits (to include their names, creation, and usage) nor may you link to websites which provide this information or access to this content.
Note it says: you may not request information about exploits. Not mods. On top of that, let's say we assume that the additional information clause applies to both mods and exploits: now it means: you can't post mod names, how to create mods, or how to use them.
That still means you can discuss what mods do, why they behave specific ways which means that in Kueh's example:
"The reason why lagging is [increased/decreased] after modding is because the mod works like this..."
is actually a perfectly legal thing to discuss, because it does not involve names, creation or usage.
I think that most people will and do understand the spirit of the rule - but I still agree that it's ambiguous.