This constant trend to use salutations (Sir, Dear, Respected) is also a cultural difference. To you, it maybe normal to show respect to someone in a position of power over you, but as far as netiquette and western work culture is concerned, this is considered sycophancy/ ass-kissing. This is considered the hallmark of an incapable, scheming individual and not of respect. So avoid this like a plague. Instead, address people with a normal Mr./ Miss
I am from eastern culture but spend a lot of my time in western culture and this is something always annoys me. I feel embarrassed hearing people calls me sir, dear, respected etc instead I feel comfortable with mate, dude, mr; Problem is in eastern culture when we learn English, the teachers teach us salutations like sir, dear are only way to show respect.
Other day I went to the doctor and I asked how should I call you. He said call me "Sir" from my reaction when he realised that it annoyed me then he said you can call me Dr. X (his name)
Point is: To me you are a Doc, you might be a teacher/professor and for them you might be "Sir" but for me you are just a Dr.
PS: The whole post is a brilliant work. Good job on putting everything in one place.