@Grumpy_Mike, I liked your replies in that thread. I have pondered the "over-ambitious-project" inquiries that come up from time to time, but hadn't specifically considered the danger aspect; the thread in question of course had both attributes. On occasion I've made comments about starting small, breaking the project into pieces, etc. Other times I just shake my head and move to the next thread.
I enjoy helping folks out and sharing knowledge, but I don't think there's anything wrong with (a) doing nothing, after all there's no requirement to give advice, or (b) giving a warning as you did. If there's that little doubt in the back of my head that says, something just might go seriously wrong here, then I wouldn't hesitate to point that out in lieu of helping to advance the project.