Request: don't change the height of the Rendering method tool

[shutterbug]

Whenever I switch rendering methods the Rendering method selection buttons move up or down very quickly as there's no need for a Radius slider in Method C but there is one for Method A and B.
I often end up accidentally clicking on the wrong method when this happens and started rendering without realising it happened.

Wouldn't it make more sense to have the Rendering method selection buttons fixed in place so that doesn't happen?

(Just from a general UI point of view, any selection buttons that get moved around when selecting something are a bad idea)