I think object space normalmaps don't use the normals of the lowpoly at all just override them but tanget space works together with the lowpolys normals.
I'm not talking about an optimized lowpoly. I'm talking about not learning jack shit about subdiv polyflow with this method. Are you up to industry level? No. Then why are you aiming for speed rather than quality already? Not trying = not learning. (Besides, if you're really going for smarter not harder, make a lowpoly,…
Like EQ said, Your lowpoly mesh that will be using the normal map in the end needs to have the same normals as the lowpoly mesh used when baking. In other words, you can't just "soften" the edges on the lowpoly using the normal map and expect it to work. You need to re-bake with a lowpoly version with softened edges as…