Lauderdale
Not entirely correct, no 'blacklist' exists for such things over in Eurocontrol, but otherwise you are correct in saying don't yell at the peeps there, even if it's only in as much as that kind of behaviour is unacceptable anywhere. The folk in IFPS try to help to a large extent, accepting that there are folk on both ends of the phone who can be having a bad day, or whatever.
Davidoz
Try to bear in mind that IFPS only applies the requirements of the relevant states, so the 50nm DCT limit is NOT their rule, but they are required to apply it on behalf of whichever state implemented it. Shouting at IFPS for such issues is ridiculous, even if they do give in and give you your demanded route. If, when airborne, you reach that airspace, and ATC say no chance, you must fly the required route, then you can have all sorts of fuel and flight time differences, with potentially very obvious results for you, not the folk in IFPS.
Anyway, whose standard route is it that you filed? Yours? If so, when was the last time it was fully checked for compliance with the airspace requirements through which it passes?
As an example - several years ago, I was somewhat involved with a German bizjet operator who got rather agitated and loud with IFPS about a route through Germany that had been rejected, with a message indicating that it was due to a level availability problem. He disregarded this information and tried to have his forseen route forced through IFPS by shouting that it was all according to the ZKSD, so IFPS must accept it! It was then - politely - pointed out to him that the ZKSD did not take into account level availability on the published routes, and that was the reason why his route was not acceptable, and would not be accepted. A deep silence followed, and soon after, a route following the one proposed was successfully submitted.
As a general rule, it is a good idea to try talking to the IFPS staff, as they are normally more than willing to help out. Additionally Eurocontrol provides the IFPUV in an effort to help people in the real world find more correct routes.
FD