>>415754229
Well it's wrong. Shapekeys are vertex offset calculations; practically when it comes to optimization they chew up gpu resources calculating offsets all the time. Avoid using them on high polygon meshes.

>>415754302
Depends on how many polygons. Generally though: do not. Toggle stuff off. You need to use an extra draw call to seperate out the meshes but having always on shapekeys on high polygon meshes is worse.

High polygon meshes are like 50k or so.