I’m glad that you asked this question, because it prompted me to go back over the various places we discussed it and found that there are some discrepancies.
Part of this is due to the different manufacturers having different specs themselves.
Here is the bottom line from the Samurai:
Always check the tech sheet for the model you are working on, but a good general rule of thumb is that the windings should have no more than 3% variation from each other. Often half an ohm might be a decent ballpark figure, but not for this particular question.
We will tweak the course content and the quiz questions/answers to clarify all this. I changed Question 5 so that one of the windings is 12.1, which is clearly more than 3% different than 12.6.