Sorry but that does not simplify the requirements in any way. If you have relied on this then you have done it wrong and you self certification might not be valid.
The product only crossed with the EMC directive and we took the below excerpt to mean fitting an already certified and shielded PSU to power the microcontroller (both in another metal box) would be exempt.
3. This Directive shall not apply to equipment the inherent
nature of the physical characteristics of which is such that:
(a) it is incapable of generating or contributing to electromag-
netic emissions which exceed a level allowing radio and
telecommunication equipment and other equipment to
operate as intended; and
(b) it will operate without unacceptable degradation in the
presence of the electromagnetic disturbance normally
consequent upon its intended use.