The thief inate abilitys aply when solo and grouped.
now i do not know about you, but i always try and strat my parties.
and i announce at the beginning that there will b eno lots cast. if they cast lots i kick em from the group.
the only fair way is to let cpu auto split.
As a thief your gil and treasure help yoou solo. you can kill goblins all day fo no exp and no cyrystals. and farm good selling stuff.
with treasure hunter you will always get a drop on no exp mob's
and good gil.