[greymule]

J/R gives 6 EXAMPLES of overthrows -- those are not DEFINITIONS.

I agree that they are not official definitions. (In fact, overthrow is not defined in the OBR book, so I guess there isn't an official definition.) However, the J/R presents the 6 categories as if all overthrows fall into one of them. If there are other kinds, the J/R should be clear that the 6 are merely examples and do not encompass all overthrows.

I can't quarrel with your reasoning to award two bases by interpreting the OP as "a kind of overthrow." But lacking something in black and white, one could also reasonably judge the OP to be a "kind of catch and carry."