Rocker oiling or lack of .

A lot of good info in this post and some confusing as well. I am in the process of putting my 408 together - Trickflow heads, HS 1.6 rockers and shafts, hyd roller. I have Hughes roller lifters that provide oiling via pushrods. What I am seeing said is oiling via shafts and pushrod can be used simultaneously without a significant oil pressure drop? Is that correct? Or should the block oil galley paths to the shafts be restricted?