Fully groves mains

What would worry me [ & why I wouldn't do it at home ] is how do you know if you have raised a burr? Cutting, grinding metal, raises the edge. The brg clearance is a little over 0.001" if you are running the customary 0.0025" gap. Any metal protruding above the surface will scratch the crank & I know of no way of the home builder accurately assessing that small amount.
The bearing material is much softer than the crank. A vertical burr on a main bearing will not scratch a crank.

Regardless, good machining practices includes de-burring after cutting. Lightly rubbing the two side edges of the cut in groove with a small hand held rasp to make a small chamfer would de-burr the groove.