Right about when I’d expect it to get into the interesting technical details, the article pivots to marketing fluff. Hoping for a follow-up that dives in.

You can achieve a gaussian blur effect using an infinite impulse response thing[1]. Some very clever people at IBM came up with the idea, and some other very clever people translated that code to Javascript and stuck it on GitHub for the rest of the world to use[2].

[1] - https://en.wikipedia.org/wiki/Infinite_impulse_response

[2] - https://github.com/nodeca/glur

Not completely buying this. He's claiming that it's better to do vector based feathering, but it's not at all clear that his approach isn't just as computationally expensive, or more. Filters do require a lot of calculations, but they are embarrassingly parallel and also you get help from the Convolution Theorem.

The 2D Gaussian blur is separable into 2 1D convolutions which is much faster than the 2D version so less of a performance issue.

I'm a bad person who read too many old comics - I thought this was a Victorian history snippet about tar-less "tarring & feathering", perhaps with honey for a gourmet twist ...

I'm confused, can't you accomplish the same effect with simple gradient (+ offset)?