I don't know about the author, but I recently saw an article where the author of Claude code apparently spins up multiple instances at once (note that it could have just been a marketing ploy to get people to use more tokens)
Just use Git worktrees and a lightweight VM environment (I like macOS native sandbox-exec) and you can spawn as many sessions as you want. I've run upwards of 30 at once on my M2 Pro with no noticeable resource impact.
I would love to know more, but am so ignorant about working with multiple sessions running in parallel that I don't know where to start - do you have a blog or published article to share that might get people like me into a more educated space
I tend to have multiple sessions running when doing stuff with CC. But rarely in the same space / domain. I'll have one working on some programming task, another making changes to my NAS and another doing research for some other topic (most recently networking gear upgrade paths).