Best to ensure always, esp. in the described application, that the
Print Text [PRTTXT] parameter is established as PRTTXT(*BLANK) to
prevent overprinting [see CPI3420, for example]. The implementation of
the feature /copying/ the spool data could produce an extra line or make
a decision about what of either the "print text" data or "line data" to
include on any particular line where overprinting is present.