Originally I read your question as “pushrod” oiling not “shaft” oiling. Sorry my answer is different. I absolutely cannot run these rockers with ONLY pushrod oiling as they are not drilled to oil the shaft, and neither is the adjuster, from just the pushrod. Both have to be done to oil the shafts through the pushrod. If I was to eliminate one method due to it being overkill it would definitely be the pushrod oiling.