So, years ago I noticed ToB has a persistent and rythmic stutter on the campaign map due to the UI, with the UI disabled frametimes are flat. Now, I had played many hours and hadn't actually noticed it, but for some reason it had become much worse at some point and I could not resolve it. I abandoned the game thereafter.

Upon reinstalling the game just now, I launched a vanilla campaign and huzah, the stutters were there but not really noticeable.

Then, I install Shieldwall and they are back :(
It's the only mod I activated. So apparently this mod worsens the stutters significantly. I looked up a let's play on YT to see if someone else had the same stutters, and indeed I noticed the same constant stutter.

I have no idea why this is the case or if it happens to everyone or if the mod team could even fix it. Just letting you know I singled out the overhaul as the cause of increased stutters than frankly make it unplayable to me. Very unfortunate because this improves the game tremendeously in every other aspect.