After doing some research this evening, I found that some other horizontal trays have holes drilled to allow the return oil to flow directly into the extended sump (see image below).
However, this would somewhat appear to defeat the purpose of the horizontal baffle by allowing oil to pour out of the deep sump onto the top of the baffle during hard cornering.
On the other hand, it seems that dumping the oil on the top of the horizontal baffle would be ok for one side (oil wold flow into the center thru the doors of the vertical baffle) but on the other side the oil would pool on the top of the horizontal baffle.
It seems that the key is to get the oil from the returns into the deep sump while minimizing the size of the holes that might allow oil to get past and onto the top of the horizontal baffle.
