I personally don't think that anyone needs to post credentials.
But, when making a recommendation, one will hope that the member posting has experience with that recommendation.
BTW, just because someone is an engineer doesn't make them perfect. These same engineers produced those leaky intake gaskets, bad balljoints, sludge monsters and all those TSB/recalls............ which kinda ruins the resume. I have more respect for the R&D guys in the aftermarket solving those issues.