I'm sorry nos, I don't agree with you. Thom is absolutely right, and I'm sick of the subject, too!
Fact is, almost anything is possible
with a hack. But that isn't the point. It is the correct approach simply to say it doesn't work with a single NIC. If someone wants to expend a bit of their own effort, research it, and find out that there are documented ways of doing it single NIC style, then that is great. That comes with effort and some experience - they need to do this themselves, and be able to stand on their own two feet, not rely on the community to do it for them as it is, as you say, an unsupported config.
You know what happens when you complicate the message to a newbie user, and instead of saying "no, single NIC doesn't work" you say "single NIC isn't supported, but you can do it if you want to with some changes"? You get every newbie coming to the site wanting to set it up in single NIC mode, and rightly expecting Thom, me, and all the others on the site to help them out because we said it was possible.
The Truth and nothing but the Truth, but certainly not the Whole Truth! That's just naive. Dogmatically expounding the exact, absolute truth is diverting from the real point - spend the extra $15 for a second NIC and get over it
Path of least resistance for newbies please... it is important for uptake and to keep the volume of repetative, pointless questions down!
(and btw, Thom didn't say it wasn't possible, he said "in short, no" which is my point, there is a longer yes answer, but it would be to miss the point!)