An additional rationale for the revisions was a drop in sales, which became particularly significant by the mid-1960s. Accordingly, the revisions focused on streamlining the texts, as well as eliminating stereotypes. The books were shortened from 25 chapters to 20 and the writing style was made terser. Difficult vocabulary words such as "ostensible" and "presaged" were eliminated, as was slang. As a result of the new, more streamlined writing style, the books focus more on non-stop action than on building atmosphere, and "prolonged suspense evaporated." The books were also aimed at an increasingly younger audience with shorter attention spans. For this reason, many commentators find the new versions nothing less than "eviscerated", foremost among them being the first "Hardy Boys" ghostwriter, Leslie McFarlane, who agreed with a reporter's statement that the books had been "gutted."