We have a family joke that whenever we learn something new to us (like how to transmigrate the "soul" of one cell phone into another) we have to forget the names of a few pharaohs of Egypt. But the truth is quite otherwise: our minds are more like a cloakroom than a bucket, and every new fact we learn is like a new coat hook on which additional facts and insights can be hung.
Such is the theme of Michael LeClerc in his advice for those heading off on a genealogy trip big or small, in the New England Historic Genealogical Society's "The Weekly Genealogist" blog for 27 October (13:43, whole #502):
All too often, on many of our tours, we have folks who are not able to get as much research done as possible because they did not refresh their memories and develop a list of specific problems and questions to deal with on the tour. . . . Even if you will be consulting with professionals on your trip, the more work you do in advance, and the more familiar you are with the problems you will be researching, the greater your chances will be for success.
IOW, fortune favors the prepared mind.