It should be possible to do but depends what you are meaning by a groove, if its a square edge and flat bottom then you may run into rigidity problems unless your machine is a big solid lump.
The taper is just the angle you require, if you put in a value then press the Post Code button you will see a representation of the path and you should see if it looks like it will be correct, might be worthwhile cutting air first just to make sure that it looks like its doing what you want to achieve.
Hood