This is a word salad which has no meaning I can figure out -the first assumption was inane about bias and and a property inspection having a link.
Having reviewed many appraisals, mischaracterization of the subject was not the issue 98% of the time. The issue was lousy, often cherry picked comp selection and bad adjustments/other issues with the appraisal itself. The field inspection /other data usually did not reveal anything markedly different.
A few cases were memorable such as where an appraiser failed to mention an office building next door to subject/impact on value.
If appraisers are out there mis characterizing a subject on a regular basis, then those appraisers should be ferreted out and dropped form the agency or client use lists. A rotten apple appraiser will do that one way or another whether or not a third party inspected.
The problem is if there are too many rotten apple appraisers working ( which I can not know ). If there are, it is a symptom of a corrupt engagement system, which can not be fixed by having a third party do the inspection.