There are two ways that 5% of something can turn into 20%
While I hope they achieve their target the good way, I think the sceptics are probably right on x86 in tablets and phones — there's too much NDK stuff out there for many Android-using manufacturers to make the switch and a lot of them, along with Apple, are now used to being able to license embeddable components and design their own silicon. It's not that the architecture is always going to be behind in speed or power, just that the ship has already sailed.