that is why i recommended the core drill, you mount it in a reamer or similar handle, and can very very quickly make a new pad where you want it, this style of design is more for those that want to skip the layout stage via cad, and scribble up a crude layout on a sheet of paper, then make it fit as they go,
so 15 seconds tops for a new pad as you need it where you need it, as opposed to 30 minutes laying it out, and another 15 minutes etching it up, etc
I myself prefer to lay things out in cad, but when you need to prototype something quickly, with enough flexibility to add different order of magnitude parts (TO3 vs TO92), grabbing 2-3 blank sheets of copper that you have kicking around, cutting circular pads for junction nodes as you are laying things out, etc, can help speed it up considerably, and i would imagine is more for the realm of simpler analog circuits, (read that as not many components / node connection points)