HW profiles

On some reason I need that a same station will be able to
load with different IP addresses. (It's not about
alternate IP definitions in the same profile). While
working under address X the station must not be reachable
from subnet Y and v.v.
I supposed that the solution is to define different HW
profiles and in each ot them to define different IP
addresses for net adapter.
It was surprise to discover that net definitions from HW
Profile1 are loaded in HW Profile2.
What is the reason ? There is no problem to change IP
address (even without restart) !
Is there possibility to overcome a problem?

N.B.
Why desktop resolution (e.g. 800x600) of user A should be
expaned to the settings of user B (suppose he preferes
1024x768) ?

Al