Runic Armor/Tahm Kench Shield?

yes

however on tahm veterans scars are better becuase they give damage

both give ~ 8% effective hp for tahm with the shield but veterans scars gives 4% always and 4% with shield whereas shield only withgives about 8% shield.

but wouldn't runic armor increase the shield AND the heal he gets if he doesn't use the shield? or am i just super overthinking this