Figured I'd add on to this since it's been necro'd. Had the same issue until a comment under the farseer mod pointed out that the problem was due to the garbage collection. Draylynn over there was kind enough to provide some config changes that ended up removing the stutter for me. Attached you'll find a copy of the Vintagestory.runtimeconfig that was provided by them. You just need to extract it into the main install location. Make sure to back up the old copy of Vintagestory.runtimeconfig before you do that though.
Hope this helps you all as it helped me.
Vintagestory.runtimeconfig.zip
