Do not return originally submitted claims material to FO's with ordinary or routine
development requests. However, in complicated situations, such as complex SE tax returns,
where either the information may be needed to insure complete development, or it appears
that pertinent claims material will serve a useful purpose, send a photocopy of the
material to the FO with the development memorandum. Such situations will occur when
the evidence in file and that requested is so complex that, without the memorandum,
the FO would be unable to comply with the request or to understand the reasons for
it.