What is the skill of being able to recall to mind all of the variables involved in a situation called?
For instance, if I have to get together a bunch of documents for a lawyer, and he asks for all of my joint bank accounts and if there are a lot of them, if I can remember all of them without missing any and without having to reference anything, what is the skill called that is used for this?
I like Photographic memory:
noun
a memory that is able to retain facts, appearances, etc, in precise detail, often after only a very short view of or exposure to them
⇒ He had a photographic memory for maps.
There seems to be some scientific dispute about the value of the descriptive term "photographic memory:"
The intuitive notion of a “photographic” memory is that it is just like a photograph: you can retrieve it from your memory at will and examine it in detail, zooming in on different parts. But a true photographic memory in this sense has never been proved to exist.
So more technically Eidetic memory:
an ability to recall images, sounds, or objects in memory after only a few instants of exposure, with high precision for some time after exposure
Mnemonic Retention is probably the safest, except it has been coopted by EQ, a cybergame:
ADJECTIVE
1 Aiding or designed to aid the memory.
The fact of keeping something in one’s memory:
Everyone has a mnemonic system to help remember important things, but some people have a much more powerful and finely tuned system:
Most of us do have a kind of photographic memory, in that most people's memory for visual material is much better and more detailed than our recall of most other kinds of material. For instance, most of us remember a face much more easily than the name associated with that face. But this isn't really a photographic memory; it just shows us the normal difference between types of memory...
So how does an exceptional, perhaps photographic, memory come to be? It depends on a slew of factors, including our genetics, brain development and experiences. It is difficult to disentangle memory abilities that appear early from those cultivated through interest and training. Most people who have exhibited truly extraordinary memories in some domain have seemed to possess them all their lives and honed them further through practice.
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Somebody who understands a situation well and knows all the relevant information like the back of their hand is often described as on top of their brief, particularly if it's in a professional context (I can't find an authoritative source, but I think the phrase originates with the idea of a barrister's brief).
He was a minister utterly on top of his brief, with an extraordinary knowledge of educational research and statistics. (The Guardian, 15 July 2014)
Even without her special access, she learns much simply by doing her homework. She is always, in a phrase used about barristers, "on top of her brief." (Michael Paterson (2012), A Brief History of the Private Life of Elizabeth II)
If that were true, it is possibly as a result of May's determination to be on top of her brief. "She's such a details person, she does actually read every submission back to front," says a former colleague. "Nothing slips through. I've had civil servants say, 'She knows more than I do.'" (The Guardian, 27 July 2014)
As mentioned in the comments, you might try "details person" to describe the character trait of a person with this skill, whereas for the task of doing the necessary preliminary work and research, consider saying that someone has done his homework.
There's also on top of the details (which I think also applies in non-professional situations) and in command of the facts.
