The magnet is around an order of magnitude more powerful on the coil side versus the back, so must be Eddie/Maxwell magic mathsticism of some wizard variety. Are these style drivers typically rare earth magnets? The sticking power feels like a rare earth magnet, but I don't know that factually is the case. Perhaps the flux is unintuitive when guided well.

Is the port shape intended to increase the Reynolds coefficient... (Is that even a valid question at this limited displacement volume? Like, I don't even know how, or if, this falls between laminar and turbulent regimes, or if such a system should be modeled more like a spring and damper or something like that.) Do you think the little square volume in the lower left is intentional or a byproduct? Does this port design have a niche name specific to the zigzag?