Hi, Hammer!
Why the heck would they try to blast the hole clear when a wedge would also give them some horizontal dimension to the core they are finding?? Maybe a wedge would cause potential problems of some sort that deep in a hole that they may risk for doing exploration but may not want the cost and risk just to finish the mother hole???
Or maybe these guys(with G), if they find some gold, don't yet want to tell the market that there is a horizontal component that proves continuity over a short horizontal distance.