Toadkill,
In his autobiograpy, Saburo Sakai said he was fooled teh first time he saw a formation -- and paid for it with his eye, and almost his life.
That doiesnt mean the mistake continued to happen throughout the war, and doesnt mean anyone else would have been fooled. The 2 planes are different enough that once pilots knew the bomber models were out there, it was pretty unlikely the mistake would be made again.