The difficulty in testing these things lies in it being an historical hypothesis, and with the ethics of human experimentation. First of all, I should respond to alanf's answer...
Genes affect behaviour, and it is testable...
It might be an uncomfortable fact, but behaviour is causally affected by genes. How could it be otherwise? Genes determine our physical make up, and our physical make up is a huge factor in our behaviour (for example, congenital blindness will effect whether someone drives a car). Of course there are social factors and they matter, but just because a behaviour is influenced by culture it does not mean that it isn't influenced by genetics. When alanf says "you can't tell whether the behaviour is a result of genetic of cultural evolution" he is introducing a false dichotomy. Things can have more than one cause, and moreover it is also possible to investigate things with multiple complex causes scientifically.
The fact that we can answer some questions about genetics and behaviour doesn't mean that we can answer all of them. Likewise, not being able to answer some of them does not mean we cannot answer any: "not testable" is a wild generalisation.
Historical difficulties and ethical challenges
With all evolutionary explanations there is always the difficulty that we cannot turn the clock back and do experiments. We cannot actually do experiments to directly determine what would happen if X was different. We can only make inferences about it based on our current situation. We simply don't have experimental access to our ancestors, and we have to work around. This severely restricts what can be answered, as we often have to make inferences about dead ancestors based on their living descendants (this is true of all evolutionary theory).
With the study of non-human species there are fewer ethical barriers, one can intervene at the genetic level, or put animals in situations that would threaten autonomy were they human. With humans, ethics puts huge constraints on what experiments can be performed. One often finds situations where a hypothesis is falsifiable or verifiable in theory, but not in practice.
What this means
The consequence of this is that we must test hypotheses incredibly indirectly, making them rather weak and contingent. Still, one can add weight to them by testing lots of different associated components and use each of them as evidence in the larger argument. It's probably worth pointing out that medical science is quite atypical, here people do directly test: "does this treatment cause my patients to recover?" - elsewhere theories get support from being connected and consistent with lots of other theories and data.
In summary. Human evolutionary disciplines are particularly difficult as the experiments and theories used as evidence are quite "distant" from what is to be shown. There are significant constraints which stem from the historical nature of evolutionary theory and the ethics of human experimentation. These difficulties are probably why no experiment was expected of them.
So, to answer your final question, probably not, at least not if one wishes to behave ethically.