Bel Arg, the voice of your experience should be heard louder and more often.
Now then, someone above suggested there was not enough detail, so can I ask a different question on the same subject?
Captain, a much better pilot for his years and experience, hasn't flown a route as recently as the FO who has done little else for the last few weeks. A military range is en route and needs to be avoided as it is active, although only up to 5000 feet, is the in the area where normally the route demands a descent below this altitude as the destination is close by.
FO is native english speaker and understands the ATC comms well. Capt is non native english speaker, and finds the language difficult.
FO understands the need to avoid, if not, to remain high (too high) above the military range. He suspects the captain has not understood what ATC have said. FO reiterates and suggests a track to follow which is commonly used (in fact he learned it from a previous trip with a younger captain, and it worked well then). Captain says we are at "FL80 is there a problem or not". His tone is quite agitated and implies that he does not think there is an issue. FO says "No, there is not a problem unless we descend below 5000 feet." Captain says nothing, and a silence follows.
My question is the obvious: What would you do in that same situation?
In fact the issue was resolved when, after a period of silence the captain turned to avoid the range, roughly in line with what had been suggested. To his credit he also acknowledged that this was necessary, although that was all.
I don't think it was handled well, but I'd be interested to know what you all think you would do.