That's possibly because you were asking me, not him. Anyway, I think you're being ridiculous. I might as well respond by asking you if, had the deer been a "cyclist, police officer, child" and the road had been one with a pavement on both sides and numerous pedestrians, whether you think it appropriate *in all circumstances* to try to swerve to avoid said cyclist etc? In many cases you'll find the answer is no, because your first duty is to keep control of the car and minimise injury to a minimal number of people. Swerving drastically carries the possibility of ending up with your car travelling sideways, controllably down the road and onto either pavement. You appear to believe that you will never be in a position such that you know there will be no time to evaluate those risks possibly. Dream on.
Your next duty to society is to consider any passengers with you (which was the case with my father that night). At least on an empty country road at night there are no pedestrians to worry about, but if you think that swerving drastically to attempt to avoid an animal, losing control of the car and ending up upside down in a ditch in the middle of the Derbyshire countryside is a good idea, then good luck.
You live in a dreamworld if you believe that animals can't appear in front of you, almost as if by magic, at such a short distance that it's impossible to avoid them. It is prefectly possible for people on foot to do exactly that, let alone more agile cyclists - and in some cases at such a close distance that there simply isn't time to determine whether or not an evasive movement would be possible or successful, and importantly, remotely safe for any humans who happen to be in the car or in the vicinity.
Michael