From 11:00PM PDT on Friday, July 1 until 5:00AM PDT on Saturday, July 2, the Shmoop engineering elves will be making tweaks and improvements to the site. That means Shmoop will be unavailable for use during that time. Thanks for your patience!
A potboiler is a shoddy and quickly written novel, poem, article, or other piece of writing. In other words, hack work written for money. An author's gotta eat, right? (Hence the word "potboiler"; these were all about keeping food on the stove.)