I stated what RS232 does not specify, Jan stated what it does specify and you even have 2 suggestions for what to call your stuff.

you have a full discussion of the pitfalls and pratfalls of non-transciever 232 read here
http://www.8052.com/forum/read.phtml?id=85349

http://www.keil.com/discuss/docs/thread5471.htm refer to a non- transciever interface that someone ask "why does it not work" and Andy read it and stated:
Note that the web page you cited says,

"... allow most applications to run without level converters" (my emphasis).

If you want something that you know will work, rather than just hoping that "most" of the time is good enough, you must use a proper RS232 transceiver.

as I said above: "you will likely have a surprise when you replace the PC"

Erik