Amazing that the SPECIFIC manufacturers recommendations are being second guessed by people who have probably never flown the MD80.
Even if rudder blanking wasn't the main culprit here the difference in epr was not that significant, furthermore we're not dealing with wing mounted engines that have a lot of asymmetric affect to either contribute to or 'recover from' the sideways drift.
If you start going sideways you reduce or cancel reverse, that's what MD recommends , they were right and for a good reason, its far more important to get the rudder in clean air and working again than monkeying around with asymmetric reverse, that will just get you in more trouble.