That's not sound logic, Helmut...
Just because no one has mounted a safety case against a preferred course of action does not make that course of action a sound one.
Using dissimilar goggles in the cockpit is just wrong! (IN MY OPINION..)
It flies in the face of contemporary protocols of cockpit scanning responsibilities...and also undermines the foundation of CRM. Surely you must agree with this?
These issues were put to bed by the US Army in the 80's, and also the Australian Defence Force...when only ANPVS5 and ANVIS 6 were available...mixing tubes up front is not the answer.....