This is a question people ask quietly. It gets searched far more often than it gets said out loud in a professional setting, and the answers available online are mostly either dismissive or wildly overstated.
Here is a straight answer, including the parts that limit it.
What the tool is
I use a structured system that takes a date of birth and produces a small set of positions — five in the version I use publicly. Each position describes one aspect of how a person tends to operate: what drives them, what they keep working on, what comes naturally, what they already know, and where they find fulfilment.
It is old. It predates management theory by a long way, and it comes from a tradition of self-knowledge rather than from organisational psychology. I am direct about that origin because I would rather you know it than discover it later and feel misled.
What it is not
It is not a validated psychometric instrument. It has not been through the construct validation, reliability testing and norming that a proper assessment instrument goes through. If you are choosing a tool for selection or formal assessment, this is not that tool and I will tell you so.
It is not predictive. It says nothing about what will happen to you. Where it describes timing, it describes conditions and likelihoods, not outcomes.
It does not tell you who you are. Two people born on the same day get the same starting picture, and they are obviously not the same person. Everything after the starting picture — your history, your choices, what you have built and survived — is yours, and none of it is in the date.
That last point is the one I insist on, because it is where this kind of tool is most often oversold.
So what is it for
It is a starting structure for self-reflection, and it is unusually good at that specific job for three reasons.
It is external. When you describe yourself, you describe the version of you that you have already accepted. A structure that comes from outside puts words in front of you that you did not choose, and some of them land differently because of it.
It is specific. "You are a people person" gives you nothing. "You process by talking, and you make worse decisions when you are made to decide alone and in silence" is specific enough to act on. Specificity is what makes reflection usable.
It is fast. Two minutes for a first picture, against several sessions for a good coaching conversation. It does not replace the conversation. It gives the conversation a place to start.
How to use it properly
Read it as a set of hypotheses about yourself, not as findings.
Take each statement and test it against actual evidence. Where has this shown up? Can you name three occasions? If yes, you have learned something about a pattern you were already living. If no, discard it without ceremony. Discarding the parts that do not fit is not a failure of the tool; it is the correct use of it.
The parts that produce a small flinch of recognition are usually the useful ones. Not the flattering parts. The ones you would rather not have seen in writing.
Why I use it in leadership work at all
Because the alternative most leaders have is worse.
The standard approach to knowing your own leadership pattern is feedback, and feedback is heavily distorted by the time it reaches a senior person. It is filtered by politics, softened by hierarchy and shaped by what people think you want to hear. Most directors are working from a picture of themselves assembled from the most polite available information.
A structured starting point that owes nothing to your reporting line is a genuinely useful counterweight. Not because it is more accurate in some absolute sense, but because it is wrong in different directions than your feedback is, and comparing two differently-wrong pictures gets you closer than either alone.
That is a modest claim, and it is the one I am prepared to make.