In one case it kicked someones birthdate to a new calendar year and his pension kicks in a year later as a result.
They always joke the donkey was slow and cost him an extra year of work.
Mean for sure but between the 15yo in question being a woman in a college environment and this only happening in front of 1/10th of 1/4th of the undergraduate student body I doubt it was of any practical hindrance.
Rushing through undergrad is possible if you do nothing but grind homework and study and read.
Grad school requires you to spend hours and hours in a lab, ass-in-seat, doing research. You're no longer competing with beer pong champions. Unless you're an absolute genius at finding the right direction to solving a novel problem, you're not going to get dramatically better results than your peers. And even if you are, you might be unlucky, and end up wasting a lot of time going down the wrong rabbit-hole.
EDIT: Almost forgot: I did skip a year during elementary, not sure about her case.
What a coincidence, me too!!
Going forward, this is now my official excuse...
For "elementary" grades it would be primarily by function (can read? can write? can count?) rather than age. And it would not be uncommon to have a much older kid from a poor family sit with little kids at the "cannot read" table.
In this setup jumping a grade could be as simple as sitting at the next table. Can read -- go there. Can count -- one more step. Physical development came from carrying water, herding cattle, bringing and splitting firewood, etc. outside of school.
And the grades mix/don't mix on their own volition at lunch and recess, anyways.
To give you a better perspective, if you were traveling back then, border control will be the only deciding body of whether you make it or not. Nowadays, you only show up at the border if the "State" has determined that you are admissible. Border control still has a say in the matter but that's power is getting smaller and smaller.
It's a paradox, because while the bureaucracy has increased and ossified, there was a lack of accountability back then. If the teacher of that school decided that you are inadmissible, you are pretty much out of option.
Finally, here is an excerpt from Wikipedia to show you how much things have changed:
> During World War I, European governments introduced border passport requirements for security reasons, and to control the emigration of people with useful skills. These controls remained in place after the war, becoming a standard, though controversial, procedure. British tourists of the 1920s complained, especially about attached photographs and physical descriptions, which they considered led to a "nasty dehumanisation".[19] The British Nationality and Status of Aliens Act was passed in 1914, clearly defining the notions of citizenship and creating a booklet form of the passport.
Those schools existed for two reasons: a) to teach kids how to read and write and some very basic math b) find ones with potential and connect them with benefactor to sponsor theirs more advanced education