It appears that Semantic Forests is intelligent enough to handle questions given in plain English. One of the authors of Semantic Forests, Patrick Shone, was also one of the inventors of an NSA-patented system for eavesdropping on international phone calls, which is similar to Semantic Forests. However, the patent only became public after winning US Patent Office approval in August this year. This is not some theoretical exercise. The US has actually built and lab tested this technology, which is clearly aimed at telephone calls.
Automation is essential.
It is likely the success rate will be low, but this may not be an issue. Bruce Schneier, the author of Applied Cryptography, claims that, paired with other types of spying technology, this software could have a significant impact on people's privacy.