The table in FCL.700 certainly creates that impression however reading the text:
(c) Notwithstanding the requirement in point (b), differences training for TMG, single-engine piston (SEP), single-engine turbine (SET) and multi-engine piston (MEP) aeroplanes may be conducted by an appropriately qualified instructor unless otherwise provided in the OSD.
and
(b), a further differences training or a proficiency check in that variant shall be completed, except for types or variants within the SEP and TMG class ratings.
I think the fact that because SEP and TMG are grouped together, they appear in this context even though there are no notified differences!