Evaluating an AfD debate is something of a black art. In some cases, there is the inevitable treading on toes and breaking of eggs. Since AfD is not a straight vote, but a discussion, it is not worth counting merely numbers. I have seen a few too many articles presented to WP:DRV with the appeal being "debate closed at 10-8, should have been no consensus". This is how I weigh them up when asked whether a given debate reached an appropriate outcome. Since these scores are not directly tied to individual comments, there is no "magic ratio". The rules for evaluating an expected result follow at the end.