Back when I was a grade schooler, in a few of our classes, we had a 'propaganda unit', wherein many of the common techniques of propaganda used historically were detailed and analyzed, perhaps with the intent of inoculating students against them.
Unfortunately, the techniques studies were not the ones actually used most frequently by cultural Marxists---they were really more those of 1950s-1960s Mad Men and WWII propaganda posters. The really dangerous techniques were never described.
It is our intent to coin a phrase to describe a rather ubiquitous pattern. We will call this technique 'authorial affirmative action', with the objective being distorting the histogram of reality. How does one use this technique, one might ask?
The beauty of this technique is you never need to say a damned thing. What you do is place large numbers of non-representative characters---with a frequency vastly in excess of their frequency in reality. People generalize from fictional examples all the time, and you're directly poisoning their histograms of reality (which is to say, their estimation of how commonly class X does behavior Y). Black scientists is one of the biggest examples here---what's the fraction of blacks among eminent scientists (the only variety that usually show up in fiction or TV)?---now compare the actual fraction of such in reality. Women who can fight better than trained male combatants is another---the actual difference between male and female raw physical strength is huge, on the order of 3-4 standard deviations, granted strength is not all there is to conflict, but it's a very large factor.
Such authorial affirmative action is particularly gratuitous when it is clear that the character(s) in question could be rewritten to occupy another gender or race with a very small amount of effort---being almost like a 'product placement'. Black lesbian naval officers with supreme physical combat capabilities (Island in the Sea of Time)? I'm looking at you Mr Stirling, largely because I know that you know better. Do your editors/publishers require such things in general, or are they just still sore at you from your Draka series?
In addition, you make members of favored/protected groups never unsympathetic or low status characters. For instance, almost all the criminals on Law and Order and similar shows are white males. Gays or blacks pretty much never get to be the bad guy or betrayers. Besides corrupting people's priors, there's also the objection that this makes most fiction and dramas terribly predictable and the limited range of characterization must terrifically suck for any talented actors in particularly protected classes.
How long has it been, for instance, since a black man got to be a Bond villain---the 70s?
The bottom line on this is that persuasion isn't really about truth, it is about repetition, status, and affiliation. Anyone who uses such techniques adversely towards your group is your enemy, and you probably shouldn't support them when you have an option.