BR is nothing new ..TBS it's more of a prob these days, than it was say 30 years ago. It definitely has something to do with genetics ! Most seeds these days are bred by ID growers for ID growers, where the environment can be totally controlled. I've found that if you plant later OD, say in June, your plants are less prone to BR . It seems the bigger the plant the more prone it is to BR . Also there are a few good strains that are BR resistant. Air movement is the most important factor when trying to combat BR. I've had big fans on plants OD before. Have you ever played a round of golf somewhere and on the back 9 there's a hole that sits way down in a holler, with trees all around it, and they've installed big fans to increase air movement. Those are there to prevent various fungus from reproducing and wiping the green out !! OD growers are few, and far between these days. Peace