I am a big fan of the WDT technique when making espresso. Not only does it improve flavors but it also creates consistency in distribution, making for a more consistent cup. I have tested a number of WDT tools and this is my absolute favorite and highly recommend it. 

WDT Technique Brief Description:

The WDT is named for John Weiss, who developed the technique back in 2005 as a way to compensate for grinders, especially smaller home grinders, that produced excessive clumps. The WDT became well-known among home baristas.

“The most compelling evidence for the efficacy of WDT is a reduction in channeling,” Scott says. “When you use WDT well, you cannot only see a decrease in channelling but all else being equal, your shots should flow a little slower, which is a side effect of decreased channelling.” - Scott Rao 

Learn more about WDT here