John Weiss and I seem to often agree to disagreeRapidCoffee wrote:Hi Stephan. I'm glad you have decided to upgrade your equipment. But I do not recommend "really hard deep WDT" or pre-processing grinds in a milk jug. Unfortunately, no amount of puck prep will fully compensate for poor coffee and/or inadequate gear. You can stir/shake/whatever as long and hard as you want, and it will not change the grinder particle size distribution.
I've found that with grinders that have poor particle size distribution, that mixing it all up in a cup greatly improves the espresso. With the Sette, grinding into the portafilter directly leads to bad channeling, which goes away for me if I blend the grounds together.
My theory as to why this is so, is that grinds fly out of a grinder at high speed, and this will naturally separate light from heavy coffee particles, which then settle in a nonhomogeneous way into your portafilter. Perhaps they are unevenly distributed in a radial pattern (ie, heavy particles in the center) or perhaps it is in layers (lightest particles fall last).
Of course, a better grinder is the best solution, but you can make better espresso with a mediocre grinder, in my experience, doing the shake.
Anyway... no need to argue theories: this is easy for you to test.