Indeed - the "smearing" of the electron is just a side effect of the Uncertainty principle. The specific principle states that the location and the momentum of a particle cannot be known simultaneously (within an error range). There's also another lesser known part of the principle combining energy and time.

So in a short enough time span, there actually IS energy created and destroyed in the universe. It's happening everywhere, right now. Particle/Anti-Particle pairs are being created out of literally nothing, then destroyed (so the average energy remains zero). One result of this is the possibility of black holes "evaporating" over a long enough span, as these virtual particles could come into existence on the very edge of a black hole's event horizon, one particle falling into the black hole and the other one escaping. Since the one escaping becomes a real particle and thus adds to the energy of the universe, the one falling in must have negative energy, so the black hole actually shrinks by a tiny bit.