I see your consumer analysis, and reject most of it. You value different things than I do in a motorcycle, and everyone else's are different. I do think there is a significant environmental concern, even if dirt bikes only make a small part of it. That's why I think an engine like this needs to take over the auto industry - because you can get the power consumers demand, without the pollution. I've spent a night in Los Angeles before, and just being in the city was enough to trigger the asthma I inherited from my dad's side of the family. It was miserable, and I personally would rather that my own city didn't turn that way. There are other cities where the classic carbureted two-strokes have dominated the transportation industry, precisely because they're cheap and light and powerful. But, all that pollution means that even the non-smokers have lung-disease rates that make Los Angeles look like a pristine mountain camp. Direct-injection technology, in a very simple form, has allowed these people to run their two-strokes not only cleanly, but actually even cheaper than before. It takes about a year for them to pay off the retrofit through their fuel savings, at which point it becomes pure gravy for them. We all want cheap two-strokes, well there they are, and they're not killing people. Forget about the polar bears for a moment, there are people on the line.
Your point about reliability is, I believe, valid. Like I said, even if the super-computerized engines are more reliable somehow, the fact that a carb is easy and cheap to work on at home gives it an immense benefit for applications that need to be low-cost, such as our dirt bikes. It's less important for street bikes, and less important still for automobiles. There's a reason that cars have more computers on them than even the fanciest of "cutting edge" four-stroke bikes. There's just no way any average could afford the up-front cost of one of them if they added all the circuitry and such, and then there's the hidden maintenance that they've already had to abandon.
I think I've already stated most of the rest I wanted to say. Ultimately, while a very sophisticated DI system will do very well for larger engines, I think that a simplified injection like the Envirofit system, or an engine modification that allows carburetors to remain in service, will be the best option for motocross and off-road bikes. And think of it this way, the less raw fuel we waste out the exhaust, the more power and fun you can get per tank of gas and bottle of 2T oil!
