Wallas, unfortunately I don't think your logic, while sensible, is correct.
Our case is seemingly very straight forward and we're from a low risk country, but we've been waiting a long time now. What I find infuriating is that we were never asked for all the additional information in one go, rather an item at a time with a week or more between each request. You would think the logical way to do it would be to ask for everything required in one go.
Our move timeline has been totally messed up now, but DIAC do not give ant firm promises so it's really down to us if we gamble on making plans assuming the grant is imminent.
I think the frustration is the poor communication, which is easily addressed by the DIAC, but too late for us June applicants with Team 8.