Donovan 417 Oiling

On a Donovan 417 block there is a port at the front right side of motor that connects to the main oil gallery. I have seen some racers feed oil into this port from the remote filter AS WELL AS feeding oil into the usual adaptor at the rear of the block. doing this obviously supplies oil into the main gallery from both ends.

what is the advantage of this? and is there any disadvantage?

anyone got experience with Donovan oiling?

cheers
Dave