What you say isn't unreasonable. Part of the problem that those of us on the evo side of the debate is that we see the same canards and easily refuted weak arguments for creationism/ID coming at us again and again.
Various forms of this behaviour can be very irritating, which makes us tend to post snappily.
* The same Freeper posting the same refuted argument again and again in a thread
* An evo refutes an argument, and then sees it pop up again from the same poster in a later thread as if the refutation had never happened
* Argument by lucky dip, where a Freeper posts a succession of arguments and as each one is refuted just goes back to their favourite creationist website for more, ad nauseam within the same thread. Don't they realise how stupid this makes them (and by extension their religion) look?
* Argument by continuous cheerleading for bad arguments being posted by other Freepers, without ever actually proposing any arguments of their own.
* Putting forward arguments which could only be true if 99% of professional biologists are either stupid or liars engaged in an enormous atheist conspiracy. (the classic 2LOT argument falsifies evolution is an example of this, do the posters really think that biologists are unaware of the 2LOT?)
But you are quite right. We owe it to the lurkers and newby creationist posters who have genuinely been misled to be as factual and down-to-earth as possible, and to avoid being snappy. I fail all the time myself though.
Perhaps what FR needs is a kill file feature (grin).
I wish you well my FRiend and patience for both of us as I can use my share as well.