Hi all, I don't know if it is an already know bug but I have discovered what follows.
The bonus to XP coming from a high Intelligence score, items as rings of Wisdom, Scrolls or blessings at the altar of the Threes does not apply when the main character gains XP by completing a quest in solo mode, with no followers.
That bonus applies only when killing monsters in solo mode, or always when having a follower because of the reduction by -20%.
I did some quest about, for instance when putting some shard of fate back into the mirror: each shard provides 2K XP as a basic value.
If I have a follower and I use my boost, I get 2022 XP per shard (2.000 - 20% + 6% given by intelligence, +6% Wisdom Items and a +15% scroll that compensates and exceeds the penalty for having a follower).
If I dismiss the follower and I keep active the same equipment and scroll effect, I get a net 2.000 XP with no bonus, as if the game calculates a limit to XP.
Something is broken here!