Hi Frank,
I am honestly sorry for having read only part of your thread. I saw the discussions about the HANA revision, but I missed the other important parts.
I did not try it but I would expect that the following (roughly) should work:
go_alv_display->field_catalog()->set_data_element( iv_field_name = 'LIFNR' iv_data_element_name = 'MY_LIFNR' ).
where MY_LIFNR would by your own copy of the LIFNR data type without conversion exit.
Of course, this would only be a partial solution as it would disable the conversion exit completely for your table. Depending on what the conversion exit actually does, this may or may not make sense.
Therefore, your general concerns about conversion exits being used all over the standard are, of course, valid.
Kind Regards,
Ivo