The "fuzzy but statistical guarantees" is basically "error correction". Which is (handwavily) the difference between digital and analog computing. What you are describing is the engineer's definition of a digital computer. Admittedly, there might be interesting performance gains if we use less stringent statistical guarantees... which happens to be what is happening each time we make the transistors smaller and more susceptible to noise.

C.f. the paper that introduced the distinction between analog and "statistically guaranteed" digital in the case of classical computers (before it people were arguing that you can not build a scallable classical digital computer because of noise): by von Neumann http://www.sns.ias.edu/pitp2/2012files/Probabilistic_Logics....

The paper that did the same for quantum computers 50 years later: by Shor http://www-math.mit.edu/~shor/papers/good-codes.pdf

P.S. FYI DWave is not a scallable quantum computer. They have another "quantumy" word for what they do, so that they can keep the hype without angering people that are trying to build an actual quantum computer.