>I'd insert "in a loop" after strings, as they did some optimizatons for concatenating in a line and probably in directly following lines.

As to 'and probably in directly following lines' I don't think so



>>Generally, concatenating strings is a bad thing in .Net and a huge waste of resources. You're probably better off with StringBuilder.
>>
>>>May be it's paranoia, but assuming the original ReturnMessage is quite long, this would be waste of resources. I am thinking may be I better off using a builder and just concatenate strings here instead?
>>>
>>>I haven't run any performance tests yet, in fact, I'm deep in re-factoring today - I created a bunch of new classes and changing code to get rid of passing messages by reference around but rather re-use the new classes.
>>>