UML15 — UML2 super/Profile/Unconsistent association extension description

b) More worryingly, 18.3.5 Semantics also says "As part of a profile, it is
not possible to have an association between two stereotypes or between a
stereotype and a metaclass unless they are subsets of existing associations
in the reference metamodel." I fail to see how a profile could in fact could
cause an association between 2 stereotypes to subset an existing association
in a reference metamodel since the stereotypes do not at all inherit from
the baseClasses so do not inherit any of its properties or associations in
order to be able to subset them: this is emphasized by the MOF
representation shown in the new Figure 447.
—

Indeed profiles do not support association subsetting. This should be made
clear in the spec to avoid any confusion while using profiles.

see above