The thing is, the low-power strategy is actually working reasonably well for Nintendo. Wii U had a very rocky start but is now recovering quite surprisingly well. We can call it a kid games console all we want, but frankly there are a lot of people who play Mario Kart and the like, and targeting people who won't buy PS4/XB1 can be a very good business strategy. Certainly better than stepping under the steamroller that is PS4, the fastest selling game console in history...
The release time appears to be aimed for the finfet processes. This presents interesting opportunities -- while the PS4 and XB1 will of course shrink down to the most economical processes very quickly, they can only make use of the power reductions and the die size reductions. A Nintendo console designed for 14/16nm would be able to hit higher clocks instead, meaning that they can reach the same performance at lower die size.
Whether they are interested in using this advantage to challenge the lead consoles is something only Nintendo and AMD know at this point, but I wouldn't bet on it.