Being in financials, our book and tax system sprocs tend to be fairly large. (about 300 - 600 lines on average).
We keep all related logic wrapped in Sql Functions that are consumed by the sprocs.
I guess it depends on what the application is...
Different apps have different levels of data and procedure requirements.
Also, consider the extra lines that OpenXML and SqlXMl require...
Is anyone else even really using OpenXML ?
I love it, but I don't find many resources or marketing behind it.