Another slam dunk psychological study straight into the garbage bin.

It's very frustrating with these studies because they don't attempt to normalize anything at all. Imagine teaching derivatives and finding that some students learn faster than others. Their excuse? Oh it must be because they did fractions when making pancakes.

One of the easiest ways to create a replicable study, which they won't ever do, would be to place students who have no experience typing (which is common for every generation) and see which ones learn fastest. If you are bothered by this then we can do learning piano, filtering out any student which may have musical practice ahead of time. It would be easy to find. Hypothesis would be that those with higher IQ have a higher rate of mastery.