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Shimano’s argument, as I recall it, was that on a mountain bike (which was what it was originally designed for) the rings were ovalised in such a way that you had the lower gear at the 3am/9pm position, so it kind of induced a stamping motion to accelerate you over the supposed dead spot at 12/6. It sounds like balls, but having had a few bikes with Biopace rings back in the early/mid 80’s, they did seem to work for me, in a way. I actually quite liked them off-road but never had them on a road bike.
Not just recent, the pre-Biopace Polchlopek ones were aligned like everybody else, only Shimano had other ideas.