This thread has stayed alive surely because it's still informative, useful and entertaining. I only came across it this morning, and somehow brought to mind:
An elegant machine, from a more civilized age...
- Obi-Wan Pavoni
Regardless of whether the La Pavoni is or isn't an espresso lightsaber, for most of us who wanted to make good home espresso back in the mid '70s, the La Pavoni was the only option we could find. Mr. Tacy's comment about it being the "least practical home machine" just didn't apply back then, so we all went through that journey and figured it out. That said, there are options today that ARE more practical and straightforward, and that will likely provide a better result when you don't go all the way or if you aren't given to OCD-driven technique.
But particularly welcome, especially coming from Chris, was his confirmation this elegant design could produce espresso that's as fine as with any alternative method. Not that it's easy or - without care and effort - consistent, but this is also part and parcel of lever-users' esprit de corps (in for a penny, in for .1g).
Adding a few notes from my own experience:
* Finer-grind / lighter-tamp has also brought out the best for me.
* Longer pre-infusion works well - up to ten seconds with some coffees, and don't worry if there's no stream or drops up to that point.
* Don't pass up the LP's capability for pressure profiling during the shot! Particularly with high-toned Central American SOs and citrusy blends, pushing that lever really hard at the start then easing up after about the first third of the pull can bring some wonderful balance and depth I can't replicate with static pressure - or with the GS/3 for that matter.
* Regarding lever pressure in general, F.M.'s analogy (early in this thread) of cutting "soft cheese or fresh brownies" is great. Mostly, I just put both hands on the lever and without pressing down, just letting that weight do the work.
* The old Rocky works great with the LP. Even after using the Macap M4 and then the Macap M7K, the Rocky paired better with the LP. (Explaining this anomoly in the "...Beat the Robur" thread, it was proposed that the larger proportion of fines turned out by the Rocky may optimize performance in small baskets, but all I know is the results taste great.)
* You will likely find your shot quality is proportional to the care with which you grind / dose / level / tamp. I think the 49mm baskets (pre-Millennium) just don't leave much margin for error, and I actually sift the coffee into the basket (outside the PF) then tap the bottom corners of the basket a few times to settle the grinds (and maybe migrate the fines downward - who knows), then level and tamp with a flat bottom. (Note that Orphan Espresso's proposals for simplified preparation (outstanding and a breath of fresh air!) dispensing with much or even all tamping could well be valid for you, especially since the LP employs a flat and screw-less dispersion screen. For a while, I just skipped the tamp altogether and let the dispersion screen establish the level and "tamping" the bed as the PF tightens in. But my own mileage varied and I went back to the extra step or two, at least when using the La Pavoni.)
* A bottomless portafilter is especially rewarding with the La Pavoni (or any lever machine), providing instant visual feedback on the effects of your lever pressure. See RayJohn's hole-saw manufacturing method, which is easy, fast, and works a treat with pretty results; I wish I'd thought of that 35 years ago.