Actually no, radials don't require this...especially as they aren't even wet sump...but the point was it's a fallacy that's often bantied about in the hangar or pilot's lounge when talking about light airplane engines, and is representative of many myths regarding light airplane engine operation.
Radial engines are pulled through, incidentally, to check for hydraulic lock; some must be pulled through on the starter to protect the engine, as the starter will slip, whereas using the propeller and the leverage it provides may damage the engine. Other engines are pulled through by hand. You're right, however; a detailed discussion of that topic merits a different thread...but there's nothing to debate there, so it may be a very short thread.