not really anymore if you can make sure you get an accurate gpx of the course.
went on a century recently with ton of local roads i had never even seen. my friend had the route on his 500 and besides missing a few turns right away and having to backtrack a few hundred feet when we realized we were off course it functioned perfectly.
so while i think knowing how to read cue sheets sure is a handy skill it is rapidly becoming unnecessary as our bike computers become smarter.
my suggestion is tke the cue sheets and build yourself the route for the garmin. sorta like studying for the test (but then taking a cheat sheet with you so you can ace it).
