The underspecification was intentional, so that people may answer according to what their preferred decision theory.
Ahh, survey question. In that case may I suggest leaving the 'rational' there but removing the 'utility maxisers'. I think that would get you the most reliable information of the kind you are trying to elicit from the response. This is just because there are some whose "preferred decision theory" and specific use of terminology is such that they would say the 'rational' thing for Bob to do is to cooperate but that a "utility maximising" thing would be to defect. I expect you are more interested in the decision output than the ontology.
The first draft of the 2012 Less Wrong Census/Survey is complete (see 2011 here). I will link it below if you promise not to try to take the survey because it's not done yet and this is just an example!
2012 Less Wrong Census/Survey Draft
I want three things from you.
First, please critique this draft. Tell me if any questions are unclear, misleading, offensive, confusing, or stupid. Tell me if the survey is so unbearably long that you would never possibly take it. Tell me if anything needs to be rephrased.
Second, I am willing to include any question you want in the Super Extra Bonus Questions section, as long as it is not offensive, super-long-and-involved, or really dumb. Please post any questions you want there. Please be specific - not "Ask something about abortion" but give the exact question you want me to ask as well as all answer choices.
Try not to add more than five or so questions per person, unless you're sure yours are really interesting. Please also don't add any questions that aren't very easily sort-able by a computer program like SPSS unless you can commit to sorting the answers yourself.
Third, please suggest a decent, quick, and at least somewhat accurate Internet IQ test I can stick in a new section, Unreasonably Long Bonus Questions.
I will probably post the survey to Main and officially open it for responses sometime early next week.