Prompted me to do this:
I must stress this is not meant to be a flame war inciting benchmark, it has been done merely to allay the aforementioned bloggers fear that he expresses in this comment:
"Surely someone close to the respective projects has asked these hard questions of themselves?
Because I know the previous paragraph has to, has to, be true, then I can only assume one thing: someone has done this as an exercise...and the results were depressing. Why else would the results not be published? If Groovy or Grails was faster, even slightly so, then you can bet it would trumpeted far and wide. The fact that it's not leaves an unsettling feeling."