Good customer service - which incidentally is slowly dying a death at BA, would say the response should have been different.
Even if the staff didn't know where the best signal was (and let's face it, usually noddy could work that out - i.e where is the broadband router located!), a better response could have been given.
It's actually a pretty legitimate question. Especially since if the customer can get reception, it will make money for BA (it's charged for). Maybe making a profit isn't important at BA, just like customer service doesn't seem important.