Okay, rant time... Author, what the hell do you mean "he used triangulation"? I can't find any page where he measured anything, but let's assume he did want to know the distance to the trees he was aiming at - so he went around measuring angles, really? What the fuck for? He was so close to the target that estimating based on the number of steps it takes to reach it is both more accurate and quicker... This is even confirmed by the "strange tool" he supposedly later used - measuring distances by laser pointers can be done up to about 50m, after that it won't register the reflected signal properly. Triangulating would make sense if we were talking about a really distant object, like a ship on the horizon.
Why is it these people insist on using concepts they neither know anything about, nor are willing to properly look up and consider logically?