Hi Juan,
It is very unfortunate that so many people like the ones you encountered are so adept at wearing their blinders so tightly.
To answer your question as to why?...
The one individual threw it right in your face... "I'm not open minded because I have two automotive degrees and my credentials do not end there. They extend for decades."
and with that, they do not believe anything else is possible.
I have encountered a number of persons with similiar degrees and because of those degrees they find it impossible, even with supporting statements from other venues, to bend in the slightest bit to what could possibly be an exception to what they have been taught.
For the longest time, Einsteins theories were considered rock solid until new blood with new ideas and approaches started proving mathematically that some of those "standards" were in fact incorrect.
You try to give them information to support what you have experienced first hand and they make every attempt to turn it around on you. They are very good at reading only what they want and finding the negative in it.
The statement made regarding the moisture in the oil and the sludge, etc.. if they did the proper maintenance on those vehicles, those issues would not exist. Ron has said it, others have repeated it, the Groove is not a cure-all for poor maintenance.
We try to educate gently, when they indicate their non-receptive tendancies you have to just thank them for their time and let it go. It is difficult to communicate with someone when they have all those degrees blocking reasonable communications.
Welcome aboard,
Karl Fortner
Tacoma, Washington