Out of context on HN, it looks so. But in my experience, the original suggestion with the separate variables gets pretty hard to keep track of, and ends up making things more confusing. The `(?x)` or `/.../x` version makes it much easier to see things in their place and understand the overall pattern.
That's pretty neat, indeed I'd never heard of this, or maybe I had once but I'd forgotten about it if so. I might counter that in a very long regex you'd want to do the assembly in multiple steps, but I can definitely see the appeal of inline comments (perhaps in addition to something like that). I'll try to keep this in mind for the next time I'm dealing with regex. Thanks for sharing!