Exactly my experience too. These fleeting images are rare, but bloody hell it feels like cheating at life if most people can summon up visualisations like that at will.

Watching someone clearly just transfer what's in their mind to a drawing is just jaw-dropping to me.

Like they'll start at an arm and move along filling the rest of the body correctly the first time. No sketching, no finding the lines, just a human printer.

I can't recall it ever being useful outside of physics and geometry questions tbh