I think this would he something amazing to add to next crate, seeing as blast is so useful for excavation, it is just mind numbing to sit there digging dirt forever. Plus, there isnt really any valuable shovels, so maybe it could be rare.
Unfortunately, we will not be making this concept a reality. Due to the amount of lag 'blast' already brings, adding more tools to the list of which are allowed blast would only mean havoc for our survival servers. Maybe in the future; however, for now its a no.