As a result of this cartoon, I spent many years as a child wondering what the hell a pumpernickel was, till I ate some and realised that it was a cross between bread and anti-matter.
In this short we see Chuck Jones really coming into his own, and shrugging off animation conventions, in a way which would lead to some of his great works later in the 50's.
Warner animators had long been aware of the artistic and comic potential of 'breaking the fourth wall' and drawing attention to the fact that this was a cartoon - a construction. Tex Avery's favourite method seemed to be to have a third-party hand hold up a sign which made some comment on the action.
Jones though, took things a step further, finding other ways to intertwine the imaginary and real worlds. Although this wasn't the first time it had been used, the extended pretext of this short - that Daffy is bored with his typecasting and tries to pitch an original script to the studio boss - keeps this gag running throughout the short. In fact you can see how this cartoon, and a few others like it, could be considered the origins of the idea of toons as actors, which was made the centerpiece of 'Who Framed Roger Rabbit' nearly forty years later.
Daffy's pitch is basically a retelling of the 'Scarlet Pimpernel' story (I also spent a period of my childhood wondering what a pimpernel was) with Daffy cast as the hero. Cleverly, writer Maltese introduces another level of reality by at the same time managing to have Daffy be the hero (a rare enough event except in Daffy's early cartoons), and still have him make mistakes and take falls, as if the script is really out of his control, even though he apparently wrote it. As if he can't quite keep in control of the situation even when he's its creator.
Sylvester fills the role of Daffy's adversary (a wise choice. Bugs, for example, wouldn't have been credible).
It's a somewhat disjointed short, cutting back and forth from the story to 'real life' scenes of Daffy in the producer's office, but overall it works splendidly.
Not one of the truly great Warner shorts, but getting there.