[Arch-TK]

Coffee is extremely finnicky and its really not as easy as you think to make even a passable shot when going between baskets with different doses. Even with an Italian dark roast.

This isn't about making amazing shots of light roast coffee, it's about the difference between an acidic and a bitter coffee. If your customers are buying and drinking straight espresso (also uncommon outside of Italy and some bordering countries) then they will notice and complain. Although I guess since most people in these regions drink singles, maybe cafes dial in for the single and just YOLO the double. I don't know much about how Italian cafes are ran as I am simply not into that style of coffee nor do I live in Italy. Outside of these regions where its common to drink straight espresso, most cafes just half ass the dialing in and if you ask for espresso its usually varying kinds of mediocre to trash. Regardless, nobody uses single baskets. In the specialty cafes where you can order a straight espresso and expect something decent to amazing, you also never see single baskets and single shots just result from a split with half of the shot wasted or in another concurrent customer's cup.

Regarding Austria, it seems like countries which border Italy also seem to often do single shots too. I didnt consider this but it also doesn't surprise me.

Regarding the portafilter, the industry has standardized on 58mm group heads in the commercial setting but there are still some smaller diameter machines out there which make pulling smaller shots much easier.

There are currently almost no new commercial machines in that format but its entirely possible it will change in the future.

I for one am considering buying an adapter for 49mm baskets so I can more easily extract good light roast espresso without needing the larger doses.

[jjcob]

I know the struggle -- We have an espresso machine at home and would love to be a able to do both single & double shots, but I have never managed to find a setting that works for both, so it's dialled in to single shots. I figured that cafes maybe are better at finding a middle ground. There must be a reason why most grinders have two separate timers for single/double tap.