I'm not sure as there are varying factors to load time. I have written a great deal of code to exclude the unnecessary and thereby reduce load time and optimize mission performance. I am sure that 777 campaign missions have their own optimizations.
Elefant: I have no idea how to generate binary missions, but if possible I will definitely do so. Binary missions are obviously the result of some post processing routine. If that routine is available to me it should be a simple matter to invoke it. If it is embedded then it will not be available.