That doesn't sound right. If the imam faces Mecca, and faces the crowd too, that means the crowd's arses are pointed at Mecca when they make the salaam (kneel and bend over). Nope, that's not how they do it, though I never miss an opportunity to point my own arse that way.
Perhaps they mean when the pulpit is faced, the worshiper faces mecca. Therefore, the imam is mooning mecca. I am not familiar with layouts of mosques.