I am compelled to spend the next two hours experimenting with her ... only giving her bottled spring water, priming her boiler, coaxing the steam out of her wand, twisting her group head firmly into the socket for each shot, trying different grinds ...
My first two tries on superfine grind ended in disaster. Got an insipid liquid that looked like Turkish coffee without the flavour. My next two tries with a 5/25 and 10/25 grind but hard-packed resulted in no water at all!
Then I try 10/25 several times without packing it in (I just let the weight of the tamper do its thing, rather than try to squash it in), and things start to happen. I get a few precious drops around 15 seconds after I start the water, and turn off the water at the 35-45 second mark. I only get a small thimbleful of precious, rich, dark, creamy liquid (barely a mouthful - not quite even enough to pass as a ristretto). It doesn't seem right, but when I taste it, the flavour is sublime - an intensely sweet caramel balanced off with tangy, lemony acidity. This is almost on par with the flavour that I enjoy from a barista-made coffee from my fav Perth coffee shops Tartine or Tiger Tiger!
12/25 yields an espresso quantity in 35 seconds, but the flavour just isn't there.
I'm going to have to let common sense prevail and stop drinking more coffee - I'll try 11/25 tomorrow morning and see how that tastes - hopefully a goldilocks moment.
If you love your coffee, I would certainly recommend taking your relationship to that next step - give in to your inner barista, and get your very own Miss Silvia. As George Harrison observed, it's going to take a lot of money (for all those wasted beans) and precious time to work out how to get her to deliver the goods, but it'll be well worth the effort!