I just discovered the Record deformation Animation Button inside the Layers Menu.
In theory its a fantastic feature for my purpose but it records too many substeps resulting in very large mdd files. Since i want to use the animation inside of 3D max I also need to convert it to something like alembic which again triples the file size.
Doing around 10 brush strokes on a 500K points test model i ended with a 3GB alembic scene.
For the animation i am planning to do i want to record hundreds of brush strokes on a 8M points model. Extrapolating the data above i estimate that to be a 2,5 TB file -.-
Is there a way to make a deformation keyframe only when a brushstroke is finished or just drastically reduce the recording framerate?
edit: i found out there is an addon for blender which converts mdd to pc2. at least that bit is taken care of