When I first reviewed the Strega, I caught enough flak that I specifically stated that it was not a purist lever machine for experts, but a hybrid with wider appeal. By that time, it had already become clear that long preinfusion and declining pressure spring lever profiles were very good for lighter roasts. In particular, they made shots that tasted similar to how coffee tasted brewed, without the amplified bitters and acids, and diminished sweetness, of most regular pressure shots. The Strega and subsequent assisted lever and profiling machines made this available to everyone, not just those specializing in levers.

In evolutionary biology, there is a concept called "preadapation," when some feature that was useful in one minor context suddenly becomes the next big thing when the species evolves into new lives. Feathers, used by dinosaurs for insulation for tens of millions of yearrs, becoming useful for flying, is the standard example.

In espresso machines, we've had two very striking cases of preadapation. First, the spring lever profile as applied to lighter roasts. Second, the needle valve inthe E61, present in the patent design, and briefly used for flushing the group, suddenly getting a much more glorious second life as a pressure profiling controller.

So, when is a bird no longer a dinosaur?

Maybe an over simplification, but I would tend to think of it using more of an Occam's Razor approach. If there is a lever used to drive a piston to create brew pressure, it is a lever machine. That provides a pretty hard line in the sand for what is and isn't a lever machine despite the varying degrees of automation/derivation.

That pawns some of the messy portion off of the top level classification and into subclassing them almost in a similar style as music genres. Sure, it's rock music, but is it classic rock, indie rock, alt rock, etc... Sure it's a lever, but is it a manual lever, modern hybrid lever, spring lever, etc... and that is where it gets a little more vague.

The meticulous would still get a pass since there is a class 1 lever tucked away in the housing, but with the above logic it gets some weird mile long name like an "Electronically Actuated Automated Lever".

Is something like the Vectis just a spring lever, or is it a modern spring lever because it has 58 mm and a joystick valve? At what point does modern transition to legacy?

So here we are... back to square one in the other thread of "What is a modern hybrid lever?"