>>11310270Fuddlore has it they saw an early drawing of the ATF (pic) and thought that's going to be the final configuration of the USAF's new super stealth fighter (the later F-22), and they copied the layout, thinking "we don't know how this works stealth-wise, but we'll probably figure it out on the way".
Then the YF-22 and YF-23 dropped, and so did Mikoyan's jaw. They ripped off the wrong design!