First issue of Barista Hustle due out on the 2nd Feb, at this stage Matts intention is for it to be on extraction with a trouble shooting guide, along the lines of a flow sheet. I have no connection to this project but have followed Matt Pergers journey for some time, he is a very experienced barista pushing the boundaries, thinking out side the square and now sharing with the coffee community. Worth signing up for and a lot of good information will land in your inbox. Chester