A bit of an update!
There are tons of ways to improve the performence of meshes you wish to modify. Some games dont need super accurate normals or tangents, or if you planning on modifiyng 10,000verts+++ per tick you can cut down on normal and tangent calculations and save a ton of frame time. We try to test as many scenarios as possible with different models of hugely different vertex count, from 10 to 100,000.
Unfortunately something seems broken with the forums today so it only accepts a single image, more videos and images are coming soon:
