I do not think there is any signifigance to the last two words. Most of the time professionial, and courteous but, it is not a rigid as it appears to a lot of folks
some examples:
AviationAddict
Tower: "Delta 351, you have traffic at 10 o'clock, 6 miles!"
Delta 351: "Give us another hint! We have digital watches!"
Center: "TWA 2341, for noise abatement turn right 45 degrees."
TWA 2341: "Centre, we are at 35,000 feet. How much noise can we make up here?"
Center: "Sir, have you ever heard the noise a 747 makes when it hits a 727?"
From an unknown aircraft waiting in a very long takeoff queue: "I'm f...ing bored!" Ground Traffic Control: "Last aircraft transmitting, identify yourself immediately!" Unknown aircraft: "I said I was f...ing bored, not f...ing stupid!"
Control tower to a 747: "United 329 heavy, your traffic is a Fokker, one o'clock, three miles, Eastbound."
United 239: "Approach, I've always wanted to say this.... I've got the little Fokker in sight."
A DC-10 had come in a little hot and thus had an exceedingly long roll out after touching down.
San Jose Tower noted: "American 751, make a hard right turn at the end of the runway, if you are able. If you are not able, take the Guadalupe exit off Highway 101, make a right at the lights and return to the airport."
A military pilot called for a priority landing because his single-engine jet fighter was running "a bit peaked." Air Traffic Control told the fighter pilot that he was number two, behind a B-52 that had one engine shut down. "Ah," the fighter pilot remarked, "The dreaded seven-engine approach."
Allegedly, a Pan Am 727 flight waiting for start clearance in Munich overheard the following:
Lufthansa (in German): "Ground, what is our start clearance time?"
Ground (in English): "If you want an answer you must speak in English." Lufthansa (in English): "I am a German, flying a German airplane, in Germany. Why must I speak English?"
Unknown voice from another plane (in a beautiful British accent): "Because you lost the bloody war."
There are more here!
http://www.airliners.net/aviation-forums/general_aviation/read.main/2712835/