Speaking as a geophysicist who worked in the research end of the Australian mining industry, just the fracturing of rock itself already consumes a LOT of energy.
Thermodynamically, think of all the fracture surface area being created. If you ever studied fracture mechanics, it's essentially the same as requiring that the elastic potential energy being released by creation of new fracture surface needs to come via work from somewhere (Griffith theory).
I think this approach needs significant "lifecycle analysis" before it can be declared to be a net positive.
Thermodynamically, think of all the fracture surface area being created. If you ever studied fracture mechanics, it's essentially the same as requiring that the elastic potential energy being released by creation of new fracture surface needs to come via work from somewhere (Griffith theory).
I think this approach needs significant "lifecycle analysis" before it can be declared to be a net positive.
Just my two cents.
(Edit: typo.)