This is bizarre because it must be intentional... which did you change Render and RenderFile to only return a string?

This goes against normal Go convention, which is when an Error is possible, have a return of (Whatever, os.Error), that way we can check to see if err != nil and handle errors that way.

Please fix this! You are a GREAT asset to the go community and it would be sad if one of Go's best programmers changed convention, because if you do, others probably will too :(