In the book Black Hole Blues by Janna Levin [0], she mentions that there was one member of the LIGO project who became the "go to" person for any technical discussions because they had memorized large parts of the infrastructure. Having memorized it, they could quickly "debug" issues and evaluate proposed changes. The implication was that asking the individual was faster than having to get together multiple people and then poll them for what they thought the answer might be.

In my own career, I've spent the last 15 years working in finance technology. Many of the systems involved in this industry are legacy (with lots of patches), complex and distributed with all of the attached problems that come with them. Multiple times over that, I've seen people with excellent memories and understanding of the system be able to pinpoint problems just by taking a couple symptoms and deducing the root cause in a few minutes. It really can be a superpower.

The one down side of course is that you build this great mental model for a system that only ever exists at one firm. This can lead the situation where you become more valuable to the firm over time as fewer people remain who understand the system. In turn, your opportunity cost of leaving goes up because you would have to start from zero at your next job.

[0] - https://amzn.to/3lkSfmu