XML Validation Error

I have been working with wM 6.1 for about a month now and recently an interesting issue arose with the following scenario.
I read in a valid xml file from disk as a byte stream and convert it into an XMLNode. Next and run it through a pub.schema.validate. Works like a charm. I then

Your message was truncated.

“I then” <<…it’s like a murder mystery…what happened??>>

Well that is annoying isn’t it. I managed to figure it out…silly me. In short (in case the message gets truncated again), the problem was not dropping some fields between flow service steps: I was overwriting the expected input for one step with the output from another. Newbies…always good for a laugh or two!