In the last 8 years I would say probably only 3 or 4 I would consider a total waste of time (very small %), however I think my research skills are very thorough and this is one reason why. A lot of the guys who have high % of wasted encounters either are terribly lazy with their research or else they have unrealistic and/or extremely high expectations, artificially boosted by paying too much attention to the wrong things. We have seen numerous examples of this, including the incredibly naive belief that certain B&S agencies advertising on MERB "must be highly professional since they advertise on MERB, and MERB would only allow advertising from 1st rate agencies." This is what I call the "Idiot Factor", and if you throw out the Idiot Factor (as you must) and look only at stats from serious hobbyists who exchange info with each other, the true and accurate wasted encounter % indices are very low. In fact I think you have a better chance of being attacked and killed by a black bear than having a bad encounter if your research is thorough, careful, intelligent, and pays attention to the right things.
If you analyze thoroughly the post of Doc Holliday you will see that some of his bad encounters could have been avoided, including the one where he saw the thoroughly poorly reviewed SP out of curiousity. This would be discounted from counting under my analytical model.