Conventional Wisdom

I just finished writing a paper for a class.  I ended a paragraph with the sentence: “They ate it up like a fat kid eats cake.”  Now this arises the question: Should we be allowed – as human beings of the planet earth – to write silly things like that in papers?  I’m testing it out not only because I personally know the professor (and he knows my sense of humor) but because I believe it’s ridiculous that most professors would flip completely out if they saw that statement in a paper.  Now, if we’re talking about a paper on the horrors of the atomic bomb dropped on the Japanese, then there’s probably not much room to joke around, but if we’re talking about impressionism and symbolism – as I was – does it need to be extremely and depressingly boring?  In my eyes, a little spice here and there can’t hurt things.  Professors would argue that papers like these show your ability to write cohesive works on topics (that you don’t care about) which will eventually aid you further in life or some B.S. like that.  It might be good for them to make students bottleneck their ideas and become automatons of modern English writing, but I don’t function like that.  It’s hard for me to pigeon-hole myself into a structured writing system when I think completely different.  In a normal discourse between myself and others, I’ll throw in jokes and what-not to help get my point across.  I haven’t turned this paper in yet and won’t until Wednesday, but I’ll post any replies by the professor if I get any, so stay tuned.EDIT:  I have since had this paper returned.  100%.  The professor didn’t even mention anything about the statement above.  Go figure.