Successfully implementing a complex or sophisticated optical system usually requires more than a knowledge of optical design and ability to use contemporary software codes. To create excellent systems also requires experience above and beyond what may be learned from textbooks. It is these hard-won lessons that may be described by the colloquialism folk wisdom. It can be valuable to be aware of the warnings embedded in apparent partiality or opinions offered without apparent justification. Many times a warning may be disregarded without apparent consequences: on other occasions raising a question initiates further study and can prevent serious problems. In this paper is outlined a number of such areas. Merely bearing them in mind during the system conceptualization and design phases can improve efficiency, effectiveness, and ultimate success. Some factors considered are costs, mechanical constraints, parts choice, specification and procurement, available adjustments, initial alignment, retention of alignment, deterioration of performance with aging, and others.