The longer time period you are talking about, the closer the numeric ratio is to controlling.
But in the chronology of Jesus' ministry, an intercalary month would be very significant. So the year of slaughtering The Lamb on Pesach affects things seriously, and the calendar framework is important in debates.
The second adar, whenever used, has the effect of aligning the calendar with the sun.
It doesn’t matter too much exactly when it is invoked, as long as it is invoked somewhere in sequence. If it is delayed for a year, it has the same effect when it is finally invoked, so it really is not an issue. It doesn’t jog the sabbath out of position.