to demonstrate the manner in which how those who "see" the solution to long multiplication by simply visualising the building blocks in their mind are able to do so. My younger brother could do that when he was seven and his teachers at the time couldn't make out what on earth he was doing whenever he just wrote an answer left to right with no workings. When they asked he explained in a manner which conveyed "why are you asking me such silly questions."
I was also never able to understand how my father could provide any root of any number , within reason, after just a short delay while he thought about it. Turned out that in his teens he'd learned the log and anti-log tables.