In job interviews, I am in the habit of describing myself as a "quick study," partly because I can learn new software and processes and such fairly fast, but mostly because I've found it's a phrase that prospective bosses respond positively to.
In reality, though, sometimes it takes a long time for information to sink into my head to the point where I can actually use it on a day-to-day basis. For example, despite a lifetime of cooking for a maximum of two people*, it has taken me until now to figure out that I should cut most recipes in half.
Cutting recipes in half works really well most of the time, but occasionally I'll run into recipes that don't divide (or, for that matter, multiply) well. My family pie crust recipe, for example, is a hot-water crust that derives its tender flakiness from the fact that the dough's warmth lets you roll it out in just a few strokes, without overworking it. It is completely possible to make a half-batch, but you have to work with a certain degree of alacrity because the smaller mixture loses its heat more quickly. With a full batch, you can laze around all you like.
It would be helpful if cookbooks included information about sizing--how to tweak the baking time, for example, or what kind of pan to use for a different-sized batch. When and if I ever write a cookbook, I'm going to do that.
* Except when I invite people over for dinner or cook for an event, in which case all bets are off and I make enough food for an army.