[Haskell-cafe] Using GHC as an arrows preprocessor?

I'm making some custom arrows and I'm getting bugs when using the GHC preprocessor, but not when using the old standalone preprocessor. In order to debug this, it would be nice to use GHC as an arrows preprocessor (so converting the arrow notation into plain Haskell and outputting the converted source code); is this possible? I also noticed that GHC's builtin preprocessor generates far more intermediate combinators than the old preprocessor. The benchmark in this paper http://www.cs.yale.edu/homes/hl293/download/NEPLS-talk.pdf seems to confirm this. Is this a known issue? Thanks, Peter