Here are some diagrams which might be helpful -- snapshots of a circuit simulation. I don't have reputation to comment, but wanted to reply to the method of finding 'actual electricity being consumed' -- I don't think averaging the lines is effective, as also illustrated by these diagrams. Unless I've made a mistake, of course.
Both circuits have 24A total load. The only difference is the balancing of the 120V circuits (as a side-experiment). The sum of the legs is 36A, and the average of the legs are 18A.
Perhaps one way to measure the total load of a 120/240 system with a clamp meter, would be to flip breakers in order to test only 240V load: L1 = L2 so either leg will show total load. Then test 120V only, adding L1 + L2. For total, add 120V L1 + 120V L2 + 240V L1. Or get the 120V number by getting neutral current and doing the math.
Also note that the neutral current in the top circuit --is the 120V loads are balanced, so current on neutral "cancels"difference of 120 L1 and 120 L2.