Zimmerman trial: the prosecution's closing argument explained

If you have read accounts (such as here or here or here) of the prosecution's closing arguments in the trial of George Zimmerman for the death of Trayvon Martin, you may have wondered what is going on.  The explanation is simple.  They are following traditional legal advice:

“When the facts are on your side, pound the facts. When the law is on your side, pound the law. When neither is on you side, pound the table.”

The prosecution has neither facts nor the law on their side.  So, they are merely pounding the table.  In a few days, we will know if that was enough.