Flathead filter

[Merc Cruzer]

I agree with most:

"The oil comes out of the filter and returns to the existing passage via the new hole drilled upstream."

but why not just direct the oil coming out of the filter back to the hole in the block above the oil pan? It just doesn't seem to be a need to drill the new hole if the only purpose is to have the oil from the filter return there rather that back through the original hole in the lower block?