I can tell you now what they mean by a lack of social reciprocity (they're also going to explain each criterion in-depth in the new book, as per their words), and none of which are related to mimicking other people (mimicking is no different to using rote memory to remember the "right" thing to say).
There's,
aloof (totally ignoring others)
passive (accepting approaches by others but not initiating them)
active but odd (talking in the one-sided way and not "giving and taking" of normal social interaction)
Quote:
3.2 Impairments of social interaction
3.2.1 The aloof group
This is the most common type of social impairment. Behavior may include:
* Behaving as if other people do not exist;
* Little or no eye contact made;
* No response when spoken to;
* Faces empty of expression except with extreme joy, anger or distress;
* No response to cuddling;
* If something is wanted, carers' hands may be pulled towards the object;
* May respond to rough and tumble play well, but when this stops return to aloof pattern;
* Seem to 'be in a world of their own'.
3.2.2 The passive group
Least common group, features include:
* The child accepts social approaches;
* May meet the gaze of others;
* May become involved as a passive part of a game.
3.2.3 The active but odd group
Children of this group make active approaches to others but make that contact in strange ways, including:
* Paying no attention to the other party;
* Poor eye contact although sometimes may stare too long;
* May hug or shake hands too hard.
3.2.4 The over-formal, stilted group
Seen in later life, this behavior is common in the most able person with autism. The following characteristics tend to be displayed:
* Excessively polite and formal;
* Have a good level of language;
* Try very hard to stick to the rules of social interaction without really understanding them.