"Borders"

I think tale 48 in the comp tales book coincides well with the "writing over borders" video we watched last WC meeting. We must be conscious and considerate of the fact that writing does not only vary across languages, but even the same language in different areas. Not only within the line of phonology and morphology, but the common person can realize that British English is different from Jamaican English, which is different from American English. Even within our own borders, there are regional differences that can obstruct communication between a person from say the deep south and someone from Idaho. Thinking about the word "borders" in relation to physical borders such as between North and South Korea, or even societal borders such as religion, makes me take into consideration the fact that all of these "borders" create the person whose writing I'm to grade. On a more professional level, if I'm ever reading a candidate's application for a job am I to take into consideration their "borders" background, or should I hold them to the same level as everyone else as the recruit in comp tale 48 did? Where should the line be drawn, and are exceptions to the rule beneficial?