Duke William of Normandy won the battle because was well prepared and had a good army. They prepared carefully for the battle. The Normans had knights on horseback who were skilful fighters.
A utility knife, metal ruler, and a hammer can be faster than trying to carefully saw an opening. Score the drywall a couple times till you are most of the way through, then just knock a hole with the hammer and break the drywall back at the score lines.
Using tape. Holes that are too large to spackle but no more than 2 to 3 inches across can be patched with drywall tape and compound. Step 1. Use paper tape or fabric mesh tape to cover the hole. Step 2. Spread a layer of compound around the hole and press short pieces of tape into it, covering the hole.