I think its not a very practicle approach, although it is a very polite and professional way of approaching a boss. Since most of the corporates have a slab for each designation, it may not be very practical to expect something beyond the given range. The employee can internally investigate and compare his bonus/increment with other colleagues. If he thinks that he has got less bonus/increment, he can approach his boss and figure out what went wrong, by using some of the steps mentioned here.
