In the image accompanying your post #5 (above) there is text beneath that states:
External Quote:
Figure 2: Image of the Dnipropetrovs'k FIR, CTA 2 and 4, the flown (red line) and ATC cleared (dotted red line) route of flight MH17. Also the aircraft type and flight level of the three commercial aircraft flying in the same area are shown. The image depicts the situation at 13:20 hrs.
I highlighted the phrase "ATC cleared" for emphasis.
An ATC clearance is usually at the request of the flight...OR is a procedural thing, because...it is at a certain point in a flight.
It is not an "order". (Perhaps the use of the term "ordered" in post #2 might lead to confusion about how Air Traffic Control actually operates, and its co-ordination with flights in the air (and on the ground) over-all?).
Air Traffic Control can impose an "order" (in a sense) on a flight IF it is necessary to provide adequate separation standards, or (for instance) other things, such as a
Holding Pattern for traffic control purposes.
So....yes, ATC
can "order" (better term is "impose") restrictions and directions. This, besides the examples above, can include speed and altitude restrictions at certain geographical points as well.
Sorry it's so complicated....difficult to express in simple words.
There is a movie titled "
Pushing Tin" that came out in 1999. Overly dramatic, but a good insight for non-pilots.
(EDIT): The movie mentioned above is more about the frantic and highly-paced function of an Air Traffic Controller in the 'local' environment...where the airplanes are MUCH closer together than in the High Altitude sectors of airspace.