The difference in opinion between Mr. Turnbull and I seems overwhelming. In fact it can at times be hard to believe that we are talking about the same thing. I have begun to suspect that we are not.

While I’m talking (and dreaming) about a transportation system that in due course will more or less replace our existing system of highways and arterial roads (and railroads), offering real improvements to its users; my impression is that Mr. Turnbull sees dualmode merely as a supplementary means to lessen the mounting traffic chaos now looming on the horizon. So our differences could originate largely from the expectations we have of what a dualmode system could and should do. Differing expectations also explain why we do not emphasize the same things from Mr. Reynolds recent paper. It’s all in the eyes of the beholder.

It’s also entirely in the eyes of the beholder if my proposed dualmode encouraging taxation scheme can be categorized as massive and draconian. Such taxation schemes, pursuing different goals but otherwise identical, already exist in many nations. An established order already an accepted reality for millions of people can hardly be described as draconian. Anyway, we are talking about a 10 to 20 percent sales tax on conventional cars. Would that really be the end of the world? Maybe in the United States, but certainly not in Europe.

Now to the real issue: Mr. Turnbull believes we do not have (I quote) "sufficient knowledge to make a final and lasting decision in this matter." I admit that Mr. Turnbull is correct on this one: We do not have sufficient knowledge, but could anyone inform me at what point in history we had sufficient knowledge to collectively select the internal combustion engine or any other major technology as our final and lasting choice.

Isn’t so that we will never see the day, when we are ready to make a collective decision in any matter? Isn’t more likely that someone else will choose for us? In my view, our future will be shaped more by those that dare do than those requesting further analyses. The case of the internal combustion engine validates this view. It gained favour and fame, because individuals (and companies) invented and developed it, thereby demonstrating how useful a machine it was. The universal use of the IC-engine is not an end-result of analysing pros and cons, arriving at the optimum answer. It was simply the best available.

I do not believe that we collectively have the wisdom and knowledge to solve all problems and choose the optimum transportation system for the mid-twenty-first century. Quite the contrary, I fear that the chance our chosen system will be even near optimum is a slim one. Moreover I believe there is a risk that the first operational system will force a decision upon us, whether the system is near optimum or not. First player on the field could be decisively ahead even before other players were introduced to the audience.

This is my concern and the reason why I so persistently argue for true dualmode from the outset. We can only hope that whatever system will conquer the market is capable of solving as many of our problems as possible. But will it be optimum and make perfect engineering sense? My guess is - no!

But Mr. Turnbull doesn’t want to make any final decisions at this point and he cautions us that (I quote again) "when we do start doing something, I believe it imperative that it be done so as to impose as few restrictions on subsequent development as possible". Fine, but in all fairness this should work both ways, meaning that when we do start "doing something", we should and must not select a technology that will forever exclude true dualmode.

If further analyses should validate true dualmode as "the optimum technology", it won’t do us much use, if we have already committed ourselves to one or more pallet operating systems incompatible with true dualmode. Remember that a true dualmode vehicle can easily use a pallet operating dualmode system, if we should find useful applications for limited pallet operating systems, while a conventional single mode car will forever be excluded from true dualmode guideways. If our true dualmode system would initially operate pallets – then that’s fine! But let’s not impose unnecessary restrictions on subsequent development by choosing technology incompatible (now and later) with true dualmode.

One thing I am certain of is that Mr. Reynolds and I agree on the need for early standardization. Mr. Turnbull on the other hand doesn’t find this important, telling us that it will be possible to transfer directly from one pallet operating system to another, and in that way get around everywhere. At least that was how I read the example in his paper. But what he ignores, or is unaware of, is that there are other uses for a dualmode system than the relatively few embarking on six-hour or transcontinental journeys. The freight market comes to mind, and the freight industry would very much appreciate the prospect of driverless freight vehicles.

With a number of mutually incompatible pallet operating systems the prospect of driverless freight vehicles becomes much less practicable. If vehicles (or containers) were to be moved from one pallet to another and responsibility handed over from one entity to another, we would in fact have re-invented the (by now) awfully inefficient railroad freight system. Average speeds down to the pace of a walking person have been encountered on trans-European routes. Surely we want something better.

A standardized true dualmode system would probably also steal passengers from rail-services, rendering many railroads superfluous in the long term. Again standardization is of paramount importance. Moreover, I still haven’t seen a description of a pallet operating system offering its users the prospect of automated parking. It is yet another feature we badly need, which only true dualmode promises to provide. It seems a standardized true dualmode system offers many useful features that non-standardized pallet operating systems can never hope to match.

In my last paper I included a number of user requirements and Mr. Turnbull seems puzzled that I didn’t put safety and reliability top of my list. From my reading of his comments safety concerns are one of the main reasons why he rejects the true dualmode idea. He believes it to be unsafe – or less safe than pallet operating dualmode – or maybe he finds that absolute safety will elude us with true dualmode, while it will be obtainable with pallets. I’m not sure which it is, but safety is important. No doubt about that.

Let me state it as clearly as I can: As a user I’m not overly concerned about absolute safety, nor are my fellow travelers. If they were I believe many of them would refuse to even enter a car, while the rest would behave somewhat different in the traffic than they do. No, safety is not a cause of much concern to the average traveler.

Relative safety on the other hand is a useful term that almost everyone can comprehend. And I’m confident that an improvement over our current modes of transport will be obtainable even for a true dualmode system. If this improvement will be a factor two, ten or fifty is largely irrelevant to the user-acceptance of a system, at least in the long term. Early incidents could lead to temporary setbacks, but people get used to it, as they have gotten used to the occasional aircraft crash.

Let there be no doubt: I hope our future dualmode system will improve safety with a factor fifty, but should it be with only a factor two it will do little to scare me away. After all it’s still better than the alternative. As a user I’m primarily enthusiastic about the time and money I can save, the distress I’m relieved of and the benefits of convenient transportation. Safety is on my list, yes! But not top of my list!

Last, but not least, I am being criticized for my no-compromise true dualmode enthusiasm. I have no good excuses to offer but to say: Yes, I’m a firm believer in true dualmode; I strongly believe it would be the best answer, in fact the only complete answer, to our growing transportation problems. I possess no comprehensive analyses to support my enthusiasm. I have no reports that show true dualmode to make "good engineering sense". I have only what I perceive as my common sense to back up my gut feeling.

A few miles from here we are favoured with a new structure bridging Denmark and Sweden. Before it was built comprehensive analyses and prognoses were made to ensure there were adequate need and that sound economics were applied to the project. It was, to everyone’s surprise, built on time and budget (3 bn. US$), and has been operational almost a year now. We call it "The Ghost Bridge". Traffic is below 50% of prognoses. Who could have foreseen that? My common sense could if anyone had bothered to ask.