oil supply to the rocker gear

Hi all. I am going to use hollow Manley push rods on a set of roller rockers. This will allow oil to be fed up to the roller rockers which have a gallery to oil the shaft. Is this a problem? Since oil is also fed through the shaft via the head. Or do you end up with two ways that oil is fed to the shafts instead of one way. The liters you get these days have the hole on top for oil supply to accommodate this.
Regards
Billy D...