Both sound quite appropriate; it seems likely that in the process of attempting to do some crazy awesome thing, you will run into the exact reasons why nobody has done it before; either you'll find out why it wasn't actually a good idea, or you'll do something awesome.
But there must be better ways to find out the reasons not to do it. Just doing it instead is a tremendous waste of time.
Talking to the sorts of people who would or should have tried already might be one avenue.
Here's the new thread for posting quotes, with the usual rules: