Just one correction: your employer will also know exactly who you are by just your salary alone. Chances are not everyone is making the same amount and if you say you make 100,760,000 rubles, it's easy enough to just look it up. Your co-workers of course don't have this info.

I personally liked the other trick better: the one that gives you the average salary. Or maybe median is more appropriate. The point is that it'd give you an idea of whether you are making more or less than at least half your co-workers.