Question regarding "include/svl/filerec.hxx" (potential for optimization)

Hi all,
I am currently trying to translate German comments in some files and
now I am stuck with the following (as the comments above both are identical
copies):

In "include/svl/filerec.hxx" what is the (logical) difference between
SfxMulti*M*ixRecordWriter and SfxMulti*F*ixRecordWriter?
Maybe someone of you knows some background information and is willing to
share his knowledge?

Doing some groundwork, I grepped all files for each declared class in this
header. The result is that "svl/source/items/poolio.cxx" is the only file
that seems to use some of the classes.

For three declared classes I couldn't find any usage, namely:
- SfxSingleRecordWriter
- SfxSingleRecordReader
- SfxMultiFixRecordWriter <= here is the initial reason for asking her
again ;-)

In addition, the other four files that include this header seem to not use
any class of it at all, namely:
- svx/source/form/fmsrccfg.cxx
- svl/source/items/style.cxx
- cui/inc/pch/precompiled_cui.hxx
- cui/source/dialogs/cuifmsearch.cxx

*Can these import statements and class declaration be removed? *

Unfortunately, I currently have nothing with me that could compile a whole
LibreOffice "make check", so could someone please test if anything happens
if those lines are deleted and provide feedback here?

Many thanks for your answers in advance!
Philipp