Shaw the entire article in the guardian was summarising ideas from a number of people from a variety of institutions. To Say "Via unsupported assertions, he's blasting away centuries of accumulated scientific knowledge about whxt(SP, tsk) really triggers earthquakes and volcanoes,"is simply not true
I did qualify my ststement by saying his professional assertions have to withstand peer review and that the scenarios were very plausible.
brief history of seismology It is only in recent decades that advances in equipment, data acquisition, computing power and analysis has enabled detailed analysis to occur. His basic premise is that many triggers exist to initiate earthquakes.
As a poor analogy,if you are shot with a bullet, is it the focused release of energy contained within the cartridge that does the damage, or the pulling of the trigger, or the pointing of the gun? The fact the energy has accumulated is not disputed, just the mechanism of its release.
The body of evidence for human or weather induced triggers of seismic is ever growing.
USGS induced earthquakes
anthropogenic earthquakes
earthquakes by human activity
If human activities can cause earthquakes it should come as no surprise that many other potential triggers exist,as have been outlined. Earthquakes can cause slope failure-likewise slope failure can cause earthquakes.

Erosion can create earthquakes       ( a good set of references at the end)