Unlawful dismissal and multiple actions

The Fair Work Act is Commonwealth legislation which relies for its constitutional validity on inter alia the external affairs and corporations powers; rather presumptuously in my view. Nevertheless contrary to the understanding of many, the Act contains some provisions which apply not just to national system employers (eg enterprise agreements, unfair dismissal etc) but to individuals as well. One such regime is unlawful termination (cf unfair dismissals) of employment, which is available to employees of non-national system employers. Much the same jurisdiction is conferred upon the Commission over national system employers via the general protections’ provisions.
The Fair Work Act prohibits employees from bringing multiple proceedings “in relation to a dismissal” most commonly proceedings for unfair dismissal and unlawful dismissal under the general protections provisions of the Act; see secs 725-732. However does this apply to a situation where an employee alleges a general protections breach involving a dismissal, for example adverse action for a prohibited discrimination ground (eg sec 351) and institutes proceedings in a State equal opportunity jurisdiction alleging discrimination leading up to but not including the dismissal. Applying fist principles, one could be excused for assuming that such a plan would not contravene the prohibition against multiple actions, since they *(in the case offered for illustration) target different causes of action and time.
The practical effect of this would appear to be (at least in the Commission’s view; Mr Gery Lane v Kangaroo Island Dive & Adventures Pty Ltd (2010) FWA 3939) that a national system employee may not make an unlawful termination application under secs 772 and 773 because the proper cause is a general protections’ claim.