This is very interesting. An Opinel without the locking ring would be similar, this thread makes me want to try that. When using a Pattada has anyone had close calls about the knife closing on your fingers? I presume the danger is quite small if you use the knife as it is supposed to be used, as a cutter. How difficult or dangerous would it be to use a Pattada for piercing anything or is a matter of technigue?
I'll try to address those questions.
Using the pattada type of knife, or any friction folder is just like using a slip joint pocket knife. You pull open the knife, cut with it, and push it closed. While cutting, the forces at work on the blade, keep it open. Cutting anything from a piece of rope to a sausage is exactly the same.
But...and her is the big difference, with no spring, the blade does not move at all unless there is continuing pressure on the spine of the blade. This means that if you use the point, and you push a little crooked, the blade will only close as far as it is pushed. It does not go past a point then snap shut on you. This goes as well on opening the knife. You grasp the blade to pull it open, and if halfway or one third open your fingers slip off the blade, it stays right there where you slipped off. Again no snapping shut. I think there is a very good reason these friction folders and penny knives have been popular for a thousand years or two.
My odyssey to the friction folder began a few years ago at a lunch where a member of our Vespa scooter group had his family there. Pascal is born and bred Frenchman, and when I was using my Opinel at lunch, a conversation broke out on knives and European style folders. Pascal thought it funny I was engaging the locking ring for such a mild job as slicing some nice fresh French bread. He pointed out that he nor his father and brother bother with the lock, and the locking ring was not brought out until 1955 for the Opinels. While there are still folding knives used in France that are like Opinels with no lock. People just take care while using, and there is no problem. Technique wins over no springs.
So when I started to play with Opinels as an experiment, I snugged up the rivet and did without the lock. I encountered no problems at all. In fact, I got so used to the springless friction folder, I started to look at my American style slip joints and saw how the spring actually could be seen as not only non functional, but dangerous. And I did use the point of the Opinel, I just was careful in my technique. With the Pattada, the sharp almost needle like point catches in what it is stuck into, and as long as you push strait in, it pierces just fine. You can feel it when it's right, and if it starts to get out of line while you pierse, the friction type mechanism lets you correct while doing it. In a weird way, it's more predicable and instinctive to use a friction folder. It's a mush over instead of a sudden snap that ends with a blade closing on your fingers like a guillotine. I hope I'm making sense. You can open it one hand pretty easy by bumping the butt end so it comes out a bit, (I think Opinel has a name for this maneuver) then hook the point on what you want to cut, or any surface like the table edge, tree, boot heel, and just pull it open. Not having a back spring actually makes the knife much easier to deal with. Or you just hold the blade while hooking the butt against a pocket edge, and pulling the blade all the open.
As far as the using the point of the Pattada, from what I understand of the history of Sardinia, bandits in the hills used the large Pattada's to uphold their fearsome reputation.
I hope I have been of some help.
Carl.