So I would differentiate between effective and non effective CRM
Agree. One of the unforeseen results of the whole CRM game, is personality conflict on the flight deck. Where it occurs, both pilots are reluctant to dob in each other mainly because management sees that as making waves and whoever writes the first report gets nailed as a trouble-maker. It is the old story. If you want easy life in an airline, don't make work for the next guy up the totem pole. If he makes a decision then his superior has to approve it in turn giving him work to do. And so it goes on.
One instance of so-called "good" CRM are support calls that are usually mandated in the company operations manual. Some may argue the more "support" calls by the PNF the better for CRM. Others disagree and prefer a less talkative flight deck. The Boeing manufacturers FCTM gives examples of support calls such as localiser alive, glide slope alive, approaching minimums, I have control, 1000 to level off and so on.
Operators then add their own ideas. This often leads to continuous "fly-by-mouth" chatter that can be very distracting to the PF. Verbalising mode changes, speed, height, heading outside company published tolerances calls, all add to the cacophony of noise coming through the head-phones.
For example, some operators require the PNF to call "SPEED" if the PF is even momentarily outside typical speed range tolerances of more than 10 knots above the selected speed or more than 5 knots below the selected speed. On final in moderate turbulence, it is common to see tolerances exceed momentarily and it is left to the good judgement of the PNF to assess whether the situation is serious enough to warn the PF of excess outside tolerance flying. But perceptions of what contitutes good judgement can vary considerably between pilots. Points scoring often occurs.
Readers will instantly recognise the PNF over-enthusiastic points scorer who shouts "SPEED" or "TRACKING" or "ALTITUDE" in a quite unnecessarily loud voice designed secretly to show the PF how alert he is; or worse still, to deliberately show his CRM authority while innocently claiming he as PNF is only doing his job by following company SOP to the letter.
This type of personality on the flight deck is not only irritating but potentially dangerous as he causes deep resentment in the PF who may be concentrating on flying the aircraft. Try having a bloody fool screaming "SPEED" on very short final as the PF is deliberately bleeding off speed to cross the threshold at VREF.
Using the terminology "Speed fast - or speed slow" means something to the PF. Clearly "speed slow" for example, would alert the PF that there may be an ASI problem if his own ASI shows correctly. Whereas the call of "SPEED" gives immediate cause to doubt IAS readings and a cross reference to the standby ASI may be called for. Concentration may be lost momentarily.
In every case of the Boeing recommended standard call-outs (or support calls if you wish), the observation is clear such as "Glide Slope Alive" In many company mandated tolerance "support" calls, the word "GLIDE SLOPE" is used to indicate an out of company tolerance, rather than a call of "Glide Slope Low (or High)" Operators need to review their stated tolerance calls from vague terms such as Speed, Altitude, Tracking, Sink Rate etc to something more definate such as the previous examples.
But back to the so called CRM of support calls. Deliberately loud and insistent repeated calls by the PNF are similar to offenders who tailgate when driving. They can be irritating and can drive the victim to distraction. Where it is clear that is happening too many times to be a coincidence, then after warning the offender to pull his head in, and with no change of behaviour, the PF has a duty to submit a report on the offender on flight safety grounds. The pity is that too many operators dismiss this as two kids fighting in the playground and refuse to take whatever action is necessary. Insolence on the flight deck must never be tolerated as it is a break-down in discipline. A poisonous atmosphere on the flight deck is intolerable on flight safety grounds. Those responsible for pushing the CRM barrow need also to be aware of its pitfalls.