Mark, from my experiences watching beginner students trying to cut to the line with a skill saw, is that they can't do it and they usually make a wrong cut, making the piece two small.
I prefer they leave the line and then pare to the line using a chisel. If the line is scored then putting the chisel in the scored line is accurate and precise.
A power skill saw in the hands of an inexperienced student can be a bad thing, and mistakes can be made very fast...
