Ruminations on Eggsperts

There’s a post on Climate Etc. “Death of Expertise“. I’m not  commenting on this directly. Instead, I have a very simple question: what is an expert?
Two scales come to mind, the first is that in any given subject the probability that a person will be the source of the answer is greater than some arbitrary value. That value might be text books or google. The other scale is that in any given subject, the probability that the answer given by the expert is right is greater than some arbitrary value.
So, let us examine an uncontroversial subject on which there is a wide spread consensus 🙂 boiling eggs
Using the above definitions, an expert could be described either as someone who is likely to know how long a given egg needs boiling OR someone who’s timing is more likely to be right.
So, here’s a simple** question:

How long should an egg be boiled?

The equation will include the temperature of the egg, the size of egg, the desired outcome (running to hard ratio), the atmospheric pressure and the initial starting temperature of the water, the power output from the cooker. Also relevant could be whether the egg has a hole, the hardness of water, whether salt is added to the water and obviously, whether the eggs are placed in the water and then brought to the boil or whether the water is brought to the boil and then the eggs placed in.
Then we have “disaster” scenarios, such as the shell cracking. Also eggs vary in the thickness of the shell (battery eggs are noticeably thinner). Then there is the age of the eggs,  etc.
Or perhaps an expert is someone who knows how to boil an egg? But if you asked them to e.g. boil an ostrich egg or a humming-bird egg, they will not know.
In theory our “eggspert”, having this “spertisement” in eggs would know how to boil a humming bird – or would they?
Perhaps our “eggspert” would know how to boil the common types of eggs that are boiled and have enough experience to know what factors might be relevant to deciding how long to boil them.
So, how would we decide who is our “eggspert”?
If one could get a degree in “eggspertology” or “eggspert science”, then we might conclude that having such a degree was the mark of the “eggspert”. But as there is currently no such degree, who would be the eggspert that could teach such a course? Who is there to confer “eggspertise” when there are not “eggsperts”?
Academic accreditation does not work unless there is first an academic with the accreditation to accredit those who ordain this credit to others.
So, what does a person that needs to boil some unusual or new kind of egg do? The answer, is clear: they boil eggs until they find the “right” time. This is just practical experience, but isn’t this just what “research” boils down to (no pun intended!)
But what would happen, if e.g. this test were initially completed in the summer when eggs were delivered at room temperature, but then it was repeated in winter when the same (unheated) delivery van delivers them at well below room temperature?
So, perhaps we might guess that an “eggspert” is someone who is more than likely to know how “things” affect boiling eggs.
But what if those eggs were not bird eggs, but fish eggs, crocodile, turtle eggs?
Perhaps our eggspert is someone who has a theoretical knowledge of the process by which eggs denaturise and become hard, who is able to take this knowledge and apply it to areas where they had no practical experience?
This implies some kind of “deeper understanding” than just practical experience. But I am still struggling to know how to judge “deeper understanding”, except that when someone is asked how to boil an egg – they are either more likely to know, or more likely to be correct.

**As I’m sure you will appreciate this is an ironic statement as I’m sure marriages have been destroyed over the “mere” matter of how long to boil eggs. Add to that the making of porridge and whether to put the milk into tea first*** and it is surprising that any marriages last.
***Milk should go in first, because otherwise it does not get properly stirred as the tea is poured in. This however requires a level of eggspertise that is often missing in the amateur tea pourer who unable to estimate the required level of milk does not have the required competence to put the milk in first.