Day Three with the Dart.
Astra green SP blade, Nanny's Warm Spice and a Plisson synthetic. I took more care with the angle (per Shane @blackland), paid attention to pressure and had a perfect, smooth and comfortable 2-pass shave. It's difficult to tell whether it's the soap/lather, or perhaps the Astra is thicker than a Nacet blade, but there was a significant reduction in aural feedback. It's not something I often do, but I gave it the alum block test, with not a bit of sting.
Getting the technique "just so", and using a different blade made a lot of difference for me. I'll have two more days with this blade, but different soaps, and see how it works out. One way or the other, it's a very good razor.