Peppersass wrote:Jim, why are ristretto shots more fault tolerant? Is it because they're less likely to be overextracted, or is the finer grind more resistant to channeling? Another reason?

Ristretto shots were a hallmark of early high end US espresso. After the almost inevitable four ounce cup of swill you got at most places, a ristretto from Vivace or any of the other top places fifteen years ago was a revelation. In those days, everyone who wanted to make good shots tended towards ristretto. It was part of the same formula as high doses and high temperatures, a part of practice codified by Schomer. At its best, you got a buttery, heavy bodied, chocolate and sherry truffle of a shot; at its worst, it was oily, thin, bitter and cutting.

About five years ago, Mark Prince posted an article claiming that ristretto shots were a crutch, that normal flow shots had a wider and subtler range of flavors, but that they were much harder to pull. This was the one of the first milestones in the trend in US espresso towards a much wider range of practice. Nowadays, people change flow, dose and temperature as a matter of course. This in turn as greatly extended the palette of coffees used for espresso.

But for a beginner, an easy and bulletproof technique is a good thing; while being able to pull exotic single origins isn't at the top of the priority list. Lower doses, ristretto flow rates, and medium temperatures make for the easiest, most fault tolerant to prep shots. Using a naked PF, it should only take a few months of making these easier shots for ones technique to become consistent enough to take on the full range of shot making. On the other hand, if you start with regular flows, high doses and no naked portafilter, you'll still be wondering in three years time why no two shots ever taste the same.