Just created this forum account to pitch in on the discussion.

I'll start by giving a short description of the issue as I've been experiencing, even if it's already been described in this thread.

In split-screen mode and after quite a few hours played, the game starts freezing / stuttering upon: 1) switching between controlled characters outside of combat, 2) linking and unlinking characters outside of combat, 3) switching between enemies in combat (ameliorated by latest hotfix), 4) creating a new controllable model (i.e. summoning) or otherwise changing your own model (shapeshift, disguise self).

Yesterday it occurred to me that what *could* be causing the stutter is that the game, for some reason, is having trouble accessing the respective character's inventory items (and spells) and needs its sweet time to load it; I assumed this could be the case for several reasons:
1) seemingly, there is a discrepancy between the time periods it takes for the game to destutter for each character, i.e. one character 'loads' more quickly than another;
2) inventory is the one thing (alongside spell lists, as I realised this morning) that grows proportionally to your time played, and it is the one thing (again alongside spell lists) that is disproportionate between different characters - your main will, naturally, have more items in their inventory if you play as them more often outside of combat;
3) spell and action lists, as mentioned in point 2 above, also grow proportionally to time played but also at a different pace for different classes; this is seemingly confirmed by my observations that spellcasters take *a lot* more time to destutter than melee characters.

I have thus far only managed to test my inventory hypothesis, and while the issue does not disappear completely, it is drastically ameliorated for characters whose entire inventory I've dumped back to camp.

I assume the issue is not entirely fixed due to said character's spell list - so I'm going to have to respec later today to test whether a smaller spell list leads to shorter freezing/stuttering.

I really hope Larian is reading this thread, because this issue needs to be resolved quickly.