Joseph – can you please cite where in the Chasam Sofer I can find the reason you gave for nittel nacht? I am referring to the statement you made about not learning due to aveilus from the birth of oiso hoish. I find it hard to believe that that is really a reason given by a halachic authority.
(I have always thought that this reason was made up by one yeshiva bochur who did not know the history of nittel nacht. It is doubtful that Dec 25th was his actual birthday – especially since the calendar changed so many times in the last 2000 years. Plus, to abolish learning due to his birth is surprising, not to mention that if it is truly due to aveilus it should continue the entire next day. But there is no need for me to expound on why I think it is not really a reason – if you can point me to where it is stated I will accept it.)
As a side point, I can see a couple of reasons not to mention the rosho’s name.
1) It is used as a swear word
2) Christ means Moshiach. By calling him Christ you are buying into their belief (albeit a minor problem with their religion – if they only thought that he was moshiach it wouldn’t be avoda zora.)