Bill Tindall, E.Tn.
Anybody can feel the benefit of a well fit drawer. A well fit drawer slides effortlessly without binding or racking.

It begins with fitting the front and back to the drawer opening in the case. Be it a rectangle (yea), parallelogram, trapezoid or whatever, I fit the drawer front to what the case presents me with for an opening. Fitting is accomplished a shaving at a time with jack plane and shooting plane. I want a uniform 1/32 total +/- on the ends and a variable amount on top depending on the height of the drawer.