Phil,
true, but.... If a small ops has just a few flights that go out of their comfort/knowledge zone, then it makes perfect sense to use someone else.
They are also a great help - if competent - to get permits and to use the correct handler, setup payment schemes etc. I use a company for these things as well mainly because my company does not like to pay up out front. They know that it costs us more (our trip supporter charges 8% on top), but they prefer it that way - their decision.
OTOH I always ask for an cost estimate and that alone has saved us a lot of money when local agents try to pull 'special fees' from where the sun donīt shine.
If longer trips pop up with short notice while youīre on the road then it makes perfect sense to use em as well to use time as efficient as possible.
So its not black or white. IMO.
If you have the operating pilot doing all the ops as well, such as flight planning, slots, handling, onward surface transport etc...the safety is compromised. The incident in Egelsbach in the Citation X is testament to that.
Sorry, that is just plain bulls.
The flight planning I always do myself, otherwise one ends up with totally stretched out plannings that donīt allow for anything going awol. (like planning on max level with LRC without actual wind - been there, done that)