And it's a bad idea to pull two shots and let them sit while you pull two others in order to serve 4 at once (or the alternative, to dose a double and let it sit while you dose a second).

There are a lot of "dumb" things done in WBC comp because of what the rules say.

Far easier to change the rules than switch to lever machines - though all the trying so far on rules changes that seem logical to many of us has resulted in exactly nothing.

Perhaps why more and more you're seeing the emergence of a new type of barista - the "Competition Barista" (who, in many cases, doesn't and sometimes has never worked as a "Bar Barista").

malachi wrote:Perhaps why more and more you're seeing the emergence of a new type of barista - the "Competition Barista" (who, in many cases, doesn't and sometimes has never worked as a "Bar Barista").

This reminds me the focus on latte art rather than good taste for a cappa, or espresso p0rn, in both cases a real shame for the profession

malachi wrote:Perhaps why more and more you're seeing the emergence of a new type of barista - the "Competition Barista" (who, in many cases, doesn't and sometimes has never worked as a "Bar Barista").

Yes, maybe there could be a handicapping system so we could all compete against the best!

matthyx wrote:This reminds me the focus on latte art rather than good taste for a cappa,

I do thank my stars that all of the baristi that pour art for me pour it over craft that they've pulled for me. So far (and yeah, I'm knocking on wood as I type) I've not had a milk artist use the fancy design to hide inadequate shots.

HB wrote:Hmm-m. Has someone taken measurements demonstrating this pressure drop, and if so, how much is it? I haven't, but I wouldn't expect a measurable drop because espresso flow rates are a tiny fraction of a rotary pump's capacity. Next time I'm at Counter Culture's espresso lab, I'll try to remember to measure their three group La Marzocco.

On my LM Linea 3AV at the Kafe if I flush another group while pulling a shot a brief about 2bar drop in pressure then back up is observed. At least IIRC the pressure comes back up before ending the flush, as I think about it not positive. Will try and remember to test and observe tomorrow time (and memory) permitting.

We tried the flush test on Counter Culture's La Marzocco FB-80, the same model used at last year's WBC. According to the panel gauge, the brew pressure dropped less than 1/2 bar when a second group was flushed while another was pulling a shot. I believe the dropoff could be further reduced by adding an accumulator, but we did not have time to test. Next time I will try to remember to bring a Scace II to confirm more accurately.

An educated palate or two could be an interesting diversion once the number crunching is complete.

For a drop of less than 1/2 bar? I believe variations in my technique would overwhelm any change introduced by such a small momentary drop in brew pressure, if such a change exists. Sorry, the effort to demonstrate statistical significance is well below my threshold of interest in the subject.

Thank you Dan, soon we will know

Well, it looks like engineers at La Marzocco really know their job

HB wrote:I believe variations in my technique ...

Gee, I was hoping for a real barista, you know, one of those consistently exceptional types that dose to 0.1g, to build the shots.