Largely personal preference. A factor that may have some bearing is if fork tines, knife points and such may protrude through the basket enough to block the spray arm.

Also, as a matter of safety, knives and forks loaded business end up have a potential for accidents ... so business end down is reasonable in that regard.

Not an expert by any means, however there some more obvious pros and cons to the different methods of loading utensils.

Loading with the handles up & business ends down:

-can result in overcrowding at the base of the basket and can allow dirty utensils to "spoon" together both of which often results in inadequately cleaned utensils

-unloading the utensils becomes more sanitary as you are grabbing the handles vs. the business end of the utensils to remove them from the basket

Loading with the handles down & business ends up:

-more room for stacking and spray angles of the business end and less chance of "spooning" of utensils

-unloading becomes less sanitary as you are grabbing the business end of the utensils to remove the utensils from the basket

It would seem that no matter how they're loaded, they would get a pretty equal amount of water spray and detergent cleaning/sanitizing When you take the potential for overcrowding & "spooning" out of the equation.

Hope this helps!

Mixing different utensils in each section, and positioning the lower part of similar utensile with something else between them or at opposite corners, also will prevent spooning.