so what you are saying is that all this is achieved from the same bolt center.
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
No, these chainrings allow you to choose one of the hole arrangements to link the chainring to the crank with.
The one you choose changes the axis of the deadspace (recovery zone) engagement with the power zone, and this provides different torque and leverage capabilities to suit.
Sounds like changing gears or having a proper crank arm length is not important anymore; but of course it is. The only time I am changing my style of riding is when out of the saddle which is normally short term so I guess I would do what I presently do; have a road bike geared for the mountains and another road bike geared for most everything else regardless of ring type. My mtb riding rarely goes over 30 miles so no real benefit unless a really long ride and that usually includes road cycling. I'd rather change gears than change bolt pattern set-up for every time I ride a different type of terrain (be it on a single ride or separate rides). I guess it also depends on expense and if the difference between each bolt pattern actually makes much difference which is hard to quantify in uncontrolled multiple variable situations. It has the scent of marketing hype that will not really affect most recreation/non-competitive cyclists. I'd be curious to know how many professional road cyclists are using these or a similar type, and use them for all types of courses whether in a one day or stage event. I only want the "setting" that provides the lowest knee stress since that is where I would keep it mounted.
That's understandable. It's just that there was no explanation of the utility in the bolt circle hole options anywhere, so I went to the source to get it and clear the confusion for everyone.
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