I took a few years off HB. When I left, WDT was understood to help folks having a hard time with even extraction but the general consensus was that if you can avoid it altogether your shots will be better.

These days I see a dozen brands with WDT tools and grinder manufacturers using WDT in videos to showcase their grinders. To me it's a sign your grinder or workflow is lacking.

What did I miss?

It depends on what you're pulling. For classic espresso with a grinder that doesn't clump, it isn't essential.

For modern espresso, where you're often working hard to increase extraction, uniformity of the puck and flow through it becomes more important. Understanding has changed significantly with progressive enthusiasts who have data to support their conclusions.

Agree with Jeff on that point. My older doser Mazzers were absolutely terrible at clumping (despite my expectation that the doser thwacking would minimize that problem). Could never get a good bottomless extraction without WDT...

I find that using a straightened paper clip works perfectly. I use the thinnest gauge wire paper clip I could find. For my money I think those fancy WDT devices with multiple needles are not really necessary. I wonder if the increasing number of needles in the newer versions of these WDT tools really makes them work better...I suspect it's aberrant evolution due to marketing pressure based on some notion that more is always better when, in fact, less is often more. Real biologic evolution has sometimes gotten carried away and produced, for example, antlers on the so called Irish "Elk" that were so outrageously large they very likely led to that species extinction.

My point is that WDT is quite beneficial. I've found a single wire works perfectly well and you should try it to see how it works for you. I don't think anyone has shown that multi-needle tools work any better, and my suspicion is that they may work even worse...

Head over to the Decent Espresso website and watch the video of John Buckman explaining WDT and the rationale behind their WDT tool. There is some good content, so it's worth the watch.

Thanks for the info. I pulled a screenshot from the video.

He describes "raking" which is just the top to essentially make the top of the grinds flat and keep the fluffiness mainly to avoid doughnut extractions even in perfectly clump-free grinds. .4mm springy acupuncture needles are on their tool.

Personally I just do a shake, but my curiosity is piqued since I have doughnuts.

bostonbuzz wrote: He describes "raking" which is just the top to essentially make the top of the grinds flat and keep the fluffiness mainly to avoid doughnut extractions even in perfectly clump-free grinds. .4mm springy acupuncture needles are on their tool.

Personally I just do a shake, but my curiosity is piqued since I have doughnuts.

I rolled my eyes the first time I saw that video about raking. But figured what the heck and decided to give it a try. Guess what, it works! Highly recommend the use of acupuncture needles for stirring. I've used paper clips, dissecting needles, etc. with mixed results. Those thin acupuncture needles for stirring and raking are the bomb.

If you're doing darker roasts then you may not need to concern yourself with all this rigmarole. If you're grinding medium and lighter roasts, give it a try and see if it works for you. Doesn't have to be fancy. My acupuncturist gave me some needles that I stuck into a champagne cork. Pretty low bling factor but it gets the job done--and donuts are a thing of the past.

Do you find doughnuts effect taste, or even measured extraction yield? I just ignore them.

Personally for me, the short answer is yes. I don't have a way to measure EY (wish I did), but as I perfected my puck prep technique, my espressos became noticeably move complex, sweeter, with better texture. Didn't need EY data, taste was my proof.

It depends on the severity of the doughnut action. If it starts to doughnut and immediately resolves and the shot goes to normal quickly then yes, it's easy to ignore. But on rare occasion the doughnut pattern lingers through most of the shot and has a negative impact on flavor.

Don't have a way to measure extraction yield. Thinking that if someone published a paper titled "The Effect of Doughnut Pulls on Extraction Yields" they might be in contention for an Ig Nobel Prize