You're right of course, I didn't explain that as well as I could have. My shop manual sez no more than 0.5 volts during a starter cranking circuit test, for example, between the positive battery terminal and the starter terminal. Then different voltages are allowable between the different ground cables and connections, between 0.1 and 0.3 volts. It all adds up though, to no more than a volt total allowed. What I've found though with good cables and clean tight connections it's pretty easy to beat these numbers. My main point was to warn that an ohms resistance test isn't very useful at all here.