I have no doubt that people have all kinds of strange abnormalities that would show up if everyone were to have a MRI however I don't think that discounts the need to be diagnosed early and given the choice of treatment.
It absolutely is an ethics issue if Docs were to withhold abnormal MRI results from a patient.

I've never been a huge fan of the "many people have MS all their lives and never know it" for several reasons. First I think it encourages people to have false hope. There is too much denial floating around anyway, just my opinion. In any event obviously I am not one of those lucky people so I need to be proactive and for me that means taking a dmd in hopes of stalling what I believe is the impending progression that comes with a chronic disease like MS.

I am also not confident that anyone can definitively diagnose MS solely based on lesions. Imvho there are far too many diseases that can produce lesions even if "they are in the spot that indicates MS". I'd bet that if we compared our MRIs the lesions are all over the place and in no particular spot.