I'm not interested in cars. Sorry, I fail to see the relevance of something with so much inefficient power and trying to compare it to a cyclist.
To me a car can be compared to a cyclist. Sure the ICE is an inefficient device and has terrible power loss through out its entire cycle but a transmission is a transmission. What is the overall difference between a car transmission and a dérailleur. Nothing, they both change gears to go faster or slower, make it easier or harder, whatever you want to call it. But can a CVT transfer the amount of torque that a dérailleur drive can transfer. Gastro said that he wants to do a wheelie, can the CVT transfer that torque and make it easier to "pop" a wheelie, or does Gastro have to work harder to do the same stuff. On my mountain bike I can remain seated and pedal enough to flip my bike over doing a wheelie. It actually isn't that hard, I just forget what gear I am in and over I go.
I am certain that, eventually, a CVT box can be made that is competitive with current mid-range derailleur systems (not everyone can afford or wants rohloff/x0/XTR/record/red or, if you're downgrading, dura ace). I completely disagree that a fit and forget box (similar in maintenance to the rohloff hub) will be harder to maintain than derailleurs which are VERY easy to trash.
If a CVT can be as easy to maintain as a rohloff hub that would be great. However, your argument that dérailleurs are hard to maintain doesn't make sense. A dérailleur is not hard to maintain, it is relatively easy to get the thing to shift correctly and get rid of the perpetual noise, if one develops. However, the ability to destroy your own equipment is based on how you ride. In 3 years of hard riding, I have yet to destroy my dérailleur. A lot of my riding is doing urban riding, jumping off curbs that kind of stuff, the rest of my riding is doing north shore style trails or XC trails. I think maintaining and destroying are two different stories.
I would say that to maintain a dérailleur is to oil the chain and make sure nothing else is wrong with it. There isn't an oil change and there are dérailleurs that have been going for 10's of thousands of miles without maintenance. Would a CVT transmission be able to handle neglect. For example, a person walks into a bike shop wants the latest and greatest bike to ride to the coffee shop for the next 30 years. He has no idea how to maintain a bike and he doesn't touch the CVT for decades. Is it still going to be as efficient as it was at the start or is it going to show signs of wear, besides the chain.
The nu-vinci is in early stages but it's a realistic alternative to limiting the number of cogs/sprockets you can fit into a space. They've admitted it's currently too big and heavy and are working to change that. I'd hazard a guess that if the housing was removed/changed to fit into a g-boxx there'd be a fairly substantial weight saving immediately.
The Rohloff is hardly traditional, especially when compared to the fairly crap (strumey archer) internally geared hubs that came before. They designed something, pretty much from the ground up, to work as a bomb proof (relatively ) MTB system. I think they achieved their design brief very well.
You say the problems with the hub - I fail to see how minimising maintenance issues is a problem. Especially with a 10-15min oil change (open cap, drain, rinse, close cap, refill) once a year being the first issue you raised.
I do agree on the proprietary twist shifter though - I've asked them to either make other types or take existing proprietary shifter systems and retrofit a double cable friction system into them but no joy there. Now there's a gap in the market for a small machine shop.
The nu-vinci hub is a great design and with some refinement could be a great alternative, but is Ellsworth going to allow other people to make a nu-vinci style hub. I mean don't they own the patent to the hub. Would there be royalty's to pay and how much would they be. If not then Ellsworth bicycles is going to be the only bicycle with a nu-vinci hub and already Ellsworth has a premium price. I know they are great bicycles but would it be worth it. Also, the nu-vinci style hub is on a cruiser kind of bike, would it be able to handle the bumps and bruises that MTB would put it through.
I agree that rohloff completed their design brief very well and I would probably not have a problem with a 10-15 minute oil change. One aspect of cycling for some people is to reduce their carbon foot print on the earth. Changing oil every year or every other year is not going to please the environmentalist in us. Maybe if rohloff found an oil that was less susceptible to break down and could last for a longer amount of time, then maybe they could use a synthetic oil, which is suppose to be less susceptible to break down of molecules.
In terms of proprietary design, what happens if your CVT/g-boxx breaks. Is this years model interchangeable with the original g-boxx or does it have different bolt holes and a different casing. Maybe in order to remain at the same level of components you have to but a new frame that fits the new g-boxx. I don't know my research into g-boxx is lacking, I admit that. Also, if you don't like the g-boxx are there other companies that make a similar product and are they interchangeable. That way it could compete with the mid-range dérailleur stock. I can change Shimano and SRAM dérailleurs out without a problem. They have the same mounting point and the same adjustments, same cable routing, the difference is in the cable pull ratio.
There are some distinct possibilities to this CVT idea. I can see the qualities that it offers to the bike community. However; I think the companies need to actually ask the bike community for their input. Like for the roadies, the system needs to be lightweight and for MTB the system needs to be able to take a hit. I think the bike community is not the professionals with an almost unlimited budget but the person with a wallet and a more down to earth kind of guy. Someone who doesn't have a car of spares following him. All of the new drive train ideas are wonderful ideas, they just need some more time to develop and people willing to try them.