I've yet to see anyone use one for the external portion of the preflight checks
Recall the story of a young flight instructor who went into the office to find his student for the next sortie. Was told "He's out at the aircraft". Instructor wandered out to find an elderly gentleman with manual in hand checking and ticking off the pre flight items. Introduced himself to find his student was Charles Lindbergh in for a check.
The manual i have says "check oil filler cap secure" and "check oil dipstick, do not operate with less than nine quarts".