Wish I could see this little firecracker when it goes off. Not to belabor the obvious, but if these things ever actually got deployed, you're looking not merely at bunker-busters, but at tacnukes minus the nuke part… here's a good rough simulator. This is serious boom. Overpressure's one thing, of course, but in any situation where we'd likely use this air-to-mud, the "chunky salsa" effect from time-on-target bombardment simply boggles the mind.
.7kt Urban Renewal comes to B.A.'s neighborhood…
But the other part of it is that such damage is actually not all that large, geographically speaking.
You could drop a .7kt charge on the middle of DFW airport, and still have buildings standing (not to mention about 340,000 very irritated neighbors). The really bad parts of the blast from 70kt on the same location wouldn't even make it to my house (which is close by). Put that in the perspective of some of the clearing operations performed in Al-Anbar, where civvies were known to have been cleared out of the way prior to engagement, and you can see why folks would like to have this as an option.