AFAIK, the THR annunciation is only a product of the THRUST button first press during Go-Around. This changes the thrust mode from THR REF to THR and commands a RoC of 2000'/min. The differentiation is this specifying a rate of climb. THR REF isn't interested in RoC - just configuration limits and FMC programming.
In the scenario mooted, the non-standard configuration (no VNAV, no pilot input etc.) doesn't have a practical application.