Black, White or Gray
Marcel T Thomas, chief executive of GE Aviation Materials who is black, has sued GE for racial discrimination; Thomas, who has been promoted three times since he joined company in 2001 and has base salary of $205,000, says recent low job evaluation and negligible compensation increase is result of racial discrimination; says racism is pervasive at GE and is seeking to have suit certified as class action; GE insists suit is specious, and notes that it has seven black officers, up from four in 2001, and that 2 of its 11 businesses, accounting for $28 billion in combined revenue, are run by blacks; suit offers example of how people can look at same numbers and draw opposing conclusions; show that no matter how race-neutral its policies, not company can be certain that it has rooted out racism, particularly in locations far from where policies are set; offers powerful illustration that employees who feel wronged will not be satisfied by diversity programs or statistics showing that others in their group are progressing; photos (M)