That's like saying that you make a copy of a book when you read it, because the words are in your memory. Or at least that memorizing passages of text is copyright infringement.
Well then could you not consider the disk copy the "archive" and the running copy the "actual" work thus creating the single copy to run in memory would fall perfectly under Fair Use? As you are allowed to make a Archive copy of the software in case it is damaged or lost, and RAM is volatile memory thus prone to loss....
There is no need to jump through hoops like that to try to justify making copies to execute. The same section of US copyright law that says making archival copies is not an infringement also says that making copies to run is not an infringement [1]. See section (a)(1) at that link.
