Doug,
Of the two recumbents I have ridden, one was a tadpole trike, the other an old Easy racer. With both I felt like I was not seeing enough of what was going on around me. It may well be that there is only a a foot or so difference in eye level but that is enough to me to miss something critical. FWIW on a road bike even in the drop position you can still sit up and get a view of what is ahead, with a recumbent you are stuck at the level you are sitting at unless you stop and stand up. I ride in fairly congested areas and need the heads up view. And yes on at least two of my bikes my riding position is almost "bolt upright" with a straight back. Recumbent bicycles and tricycles have their place and I know many people that would be unable to ride if they didn't have a recumbent. But to summarily dismiss something as a side car as dangerous and no good is a bit of stretch. Someone is always inventing a better mouse trap, but we still have mice

Aaron