Yeh alright but these new guys are looking at something else. Not sure what it is. Maybe they are pretending to know grain in relation to the new penetrant. In relation to the new ways of milling them and pressurising the new treatment. Don't know. I know the cambium a little and that it would react, swell as compared to some heartwood. Now everything is turned around for the younger cambium absorbs the gaseous chemical and the heartwood doesn't. There becomes under twist a seperation between the heart and layers. Under pressure the heartwood is required. interesting not?