Current measurment in energy meter
Your point 2 should be correct. Kirchoff's Current Law says that the sum of all the currents going into a device has to equal the sum of all the currents flowing out of a device.

Therefore, if your load only has 2 wires connected to it (hot, neutral), then there should be equal current flowing through each wire.

There is a caveat, though: many devices also have a ground connection. Under normal circumstances, I believe most devices don't allow current to flow to the ground pin. However, sometimes it does happen. If that's the case, and you're measuring only the neutral wire, you may measure less current than is actually flowing into your load from the hot wire.