I've finally realized my Lamy 2000 needs a nib touch-up, or something. It's an F, and sometimes writes like an F, but sometimes like an M. on strokes which go to the right, so much ink is dumped it looks like shading afterwards. I plan to ship it to Lamy for service, and I wrote them a note with sample left-and-right squiggles. the ones going to the left almost skip, but I'm not varying my pressure or angle.
In my note to Lamy, you can clearly see the shading effect. this was on a moleskine sticky note, and the strokes are tending to be on the thicker side. on rhodia paper, I mostly get super-thin strokes, with forays into thick strokes mid-word. the horizontal squiggles show it best on the moleskine; on rhodia, it's like that mid-word.
interestingly, the nib "sings" on rhodia paper.
the nib is never scratchy, but also not nearly as smooth as my twsbis or pelikans.
I've had this pen for about 10 months and I've thoroughly cleaned and flushed it many times. I'm now a lot more experienced with other pens, so I've only lately come to realize how inconsistent this one is.
This writing sample is with Noodler's Luxury blue. I've also used a lot of Noodler's Legal Lapis with this pen, and some Black Swan in the English Roses.