"Why Do I Dream Those Dreams" was one of Friz Freleng's early directorial efforts. In keeping with the original policy at Leon Schlesinger Productions - which released its cartoons through Warner Bros - every cartoon in the Merrie Melodies series featured a performance of the title song (the series' name was based on Disney's Silly Symphonies), while the Looney Tunes featured the studio's main stars; at the time it was a humanoid named Buddy.
Here we have an adaptation of Washington Irving's "Rip Van Winkle". It mostly follows the original story, with the henpecked Van Winkle heading to the forest and having a shocking experience. Previously the only version that I'd seen is Will Vinton's loose adaptation.
I understand that from the start, Freleng's major themes were show biz and matching music with action. I guess that with this short he was trying to find his way. The very next year he released the perceptive "I Haven't Got a Hat", best known as the very first appearance of Porky Pig (slightly chubbier than the Porky whom we now know). I suppose that this cartoon works as a before-they-were-famous outlet.