'Outlander' and 'The Knick': Once more, time is of the essence

It sometimes seems as if TV's many period dramas are simply there to make the viewer glad he or she wasn't around for that particular era. HBO's "Boardwalk Empire," for example, offers no reasonable upside to visiting Atlantic City or Chicago in the 1920s. Showtime's "Masters of Sex" strips some of the appeal away from the late-'50s, particularly for independent women. And with the dreadful "Halt and Catch Fire," AMC has managed to quell my desires for a 1983 do-over. Even "Mad Men" has artfully...