Puking Dog, thank You for the explanation.
A Squared,
here, things are handled similarly but with differences in detail when it comes to dispatchers.
Generally, our dispatchers tasks range from assigning aircraft to flights (crewing them is done by a different dedicated team in the same room), taking care of ATC matters like filing flight plans, keeping them alive in case of delays to even e-mailing missing charts or other documents to aircraft requiring them on remote airfields. The dispatchers can be considered the cockpit crews agony aunt who is called in case of all operational discrepancies. And they are usually excellent at solving them, let there be no doubt about this.
Calculating operational flight plans, logs, or whatever they may be called in different companies is within his scope as well. But in my company, he will only plan long range and some nominated other flights with higher planning needs: e. g. flights to Tripolis (due to the security situation), Erbil (dito), weight critical flights or wetlease flights will often be planned by him as well. 90% of the flights are planned by flight crews on their own though; there is a flight planning programme provided for that. Only in case of problems like a high risk of diversion, inability to use the preferred alternate, MEL items that make the use of the individual aircraft undesirable for a route, a need for an exact ZFW for performance and fuel planning etc. will the dispatcher be consulted.
The main difference seems to be that the dispatcher here will only offer well founded and worth listening to, albeit non-binding, advice. He might offer a preferred alternate, suggest different routes or whatever might be needed, but the captain has the final call and is allowed to accept or reject this. A flight plan provided by a dispatcher will have to be checked, accepted and signed by the captain; this involves a cross check of weather, notams etc. The captain is also free to decide on fuel requirements (keeping within legal limits of course!) and may order any amount of extra fuel he deems sensible, be it 0 or an amount that requires the offloading of luggage to meet performance requirements. In flight, when outside of the stations radio coverage (in absence of ACARS or HF), no assistance from dispatch is possible, so the crews are completely on their own and are required and allowed to call the shots themselves.
Of course, such freedom comes with more responsibility as well. Here, the buck stops squarely with the captain. If something undesired happens, he will have to explain this, and he will certainly be asked why he did not follow the dispatchers advice if applicable. The dispatcher in turn will be required to answer only for those points that were in his scope, but this does in no way release the captain from his ultimate responsibility for the flights safety.
An attempt to put some blame on the dispatcher is by no means a "get out of jail" card, as the captain has checked and found all the items provided by him to his satisfaction before beginning the flight.