Rounding the edges against a porcelain sink/bath or with the handle of a mallet will start to round the toe/edge junction. When you hit the toe with the mallet make sure you don't hit down onto it's edge. you don't want to round the toe as you would with the inside&outside edges of the bat i.e. when you do the inside/outside edges you can hit onto the edge at an angle to round them, when you do the toe you hit flat/straight with the face of the bat.
If you hit the wood on the toe in a way that forces the "fibers" towards the handle, they will buckle and come away as feathering