Got a job - how to do it ? :)

[magicniner]

Depends what he is doing exactly. But the corner sharpness itself is determined by the angle.

That is geometrically incorrect, if you were right a 15 degree cutter with a 3mm flat will generate really sharp corners?
The size of the flat at the tip of the cutter determines it's effective minimum diameter and directly dictates how sharp an internal corner you can generate with it.

- Nick