BACM — Use of "leg" terminology to describe relationships

It’s not clear why the “leg” construct is introduced when association classes already exist in UML and have properties instead of legs. As do n-ary associations. Though neither are part of MOF officially, I don’t see the justification of the “leg” terminology.

The term leg is defined in BACM-44 the proposal to resolve BACM-43

The term "leg" is justified because this section of the specification is defining the translation from the UML-based diagrams in the specification to MOF-compliant XMI. Since n-ary associations and association classes are not part of MOF, these forms are translated (reified) into classes and generated associations. The term "leg" designates the generated associations to distinguish them from other associations.
If BACM-44 is approved, this issue should also be resolved