Okay so I noticed two weird glitches or rather unintentional things happening while playing Geomancer with a friend.
1) Cast Geo-Poison on an enemy and defeat it. Then deactivate the Luapon with Full Circle. If a party member is nearby when you do this, he or she will be temporarily poisoned. Depending on whether or not Bolster or Ecliptic Attrition was active before you deactivated it, the poison/tic is different. I have seen 1, 2 but recently even 6/tic (since Bolster was on). The poison lasts for about 3 seconds, but it's still a problem in certain situations.
*** This is not a glitch, as it turns out this is the desired effect for using Full Circle. ***
2) I only noticed this recently but whenever I deactivate a nearly-full Luapon, I get some MP back. I don't know if this is an actual trait or not, but I can't find it on any JA or trait description in-game or on the wiki.
And here's a useful tip for you guys who need some skill+ :
If you have an adventuring fellow of your level, it's actually faster to cast Geo- spells on them. You can't target them, so you have to type the commands manually or just make a macro. Almost every time I casted Geo-Voidance or Geo-Precision on my NPC, I got a skill+.
I hope this post is helpful for any other Geomancer out there or anyone who's interested.