Mind you they'd have to have a reliable fall-back so they still work and are adjustable if (when) the power fails.
Edit: I was actually thinking last weekend when I think I over tightened my laces on my boots and my feet got quite sore that strain gauges in boots/laces might be a good thing!
That was a pretty common trick for combat boots before the laced + side zipper boots became more popular.
You don't tie as you would normal laces you create a knot on one end and loop it through all the lace loops then you simply pull and loop it around the shaft and the colar and tuck it in it was secure enough to even run in (as much as can one run with a full kit and a PRC-77 they had us chugging along during training) and traverse any terrain I had too.
I don't know how would if fare in very cold (as in sub zero) weather but then I had normal laces snap on me while trekking in Peru and Iceland as well.
BTW don't forget that while a bungee cord can stretch pretty well the shorter it is the more stiff it is so all of the bends in the loop essentially create a lot of short individual links that don't stretch as easily as the entire length of the cord unwound, you also need to overcome the friction between the cord and the tongue of the boot which makes this setup pretty darn secure but easy enough to pop on and off if your curl your foot and ankle and ease it in or out.
Edit: Actually, turns out they have been already used in sports shoes, go figure! The aesthetics don't quite seem exquisite, but the functionality seems to be all there.
For what it's worth, though, I didn't find them that much faster to put on than normal three-buckle boots.