It is peak grass pollen season here in Willamette Valley Oregon. If I am out in it, it's all kinds of not OK. In the S with Biodefense activated, its terrific. Really good. But I do have questions. I assume that anytime outside air is pulled in, including biodefense off, it goes through full filtering? True? Biodefense seams to insist that the fan is high and outside air is being pulled in (understandable). But why is the air conditioner required? Lastly, with a biodefence capable car, is biodefence mode just a short cut? I could set all the settings independently and get exactly the same results?