Psst! @Paul Kallus please check out my post on this thread from eight days ago. Also, My first post on that same thread.
I don't think it requires an area the size of a basketball court, nor a slavish devotion to realism (although I have participated in realistic operations on a couple of really spectacular HO layouts.) The technology required to support this idea wouldn't be cheap (cameras, sensor tracks, iPads, CAB-2s, operating accessories, etc.) But because the biggest cost is real estate, as long as we keep the size modest, the hardware and trains aren't a deal-breaker.
I believe Roadside America could have been saved by a comprehensive redesign along these lines. I'm also familiar with other public exhibits that applied this concept with varying degress of success.
Great minds think alike and would love to discuss further, hit me up!!
