I have noticed a pattern in a couple of recent discussions which i have dubbed "cargo-cult arguments": Basically its when one side go through the patterns which is usually associated with a real scientific argument, but its really just a scaffold.
More specifically, typically an argument take the following general form:
We observe A. A relate to C as follows (...). Therefore A is evidence against C.
Furthermore, how A relate to C can (in a proper argument) be fleshed out in the most trivial details.
What is missing in a cargo cult argument is either: clear language around the conclusion and hypothesis and (most importantly) a clearly stated, valid argument that can be made granular.
In other words, he or she "goes through the motions", introducing both valid scientific evidence A and a disputed conclusion C, and because it sound quite scientifcally he or she does not understand why its just dismissed by the other party.
What make cargo-cult argumentation poisenous for rational conversation is that when one tries to dismiss a cargo-cult argument, one usually have to try to flesh out the lacking argument and THEN dismiss it. This will seem like a strawman to the person who made the argument: He or she will think: "But thats not what i said or implied. Why does he not address my actual argument, rather than adding more to it?", and usually the debate will detoriate.
Cargo-cult argumentation typically arise in pseudo-science, and rely on supporters who are willing to quote the arguments almost verbatim without thinking them through.
The best way to expose a cargo-cult argument is to ask the person who make it to flesh it out in details before any counter-points are introduced.
It will typically cause the argument to unravel by itself, and since one is just asking for clarification, there is less chance of antagonizing the other party.