W6W,
I believe that alot of companies are using Utems, Vtems, down hole probes along with any historic info they get before they start a drilling program. I would include in the historic information, not only what a couple of explorers did 100 years ago but what has been drilled by former companies that had to abandon the site because of economics or other reasons.
Incidentally some of those probes they put down the holes can give very accurate readings in all directions for many, many meters out. I think they can do a 360 for 200 meters out. That can tell a company if they are on the right track or not BUT it does not replace infill drilling to raise the inferred tonnage grades to the indicated or above catagories.
All the best,
Jerry Francis