Mine hasn't read like I intuit it 'should' since it broke in. It's entirely common for the dash gauge to read low. I wonder if it might start reading lower in relation to the valve cover gasket fading (or something else; it's a vehicle - things get old and wear out) as it seems mine has read a little lower since I noticed oil weeping out a little at the back end of the covers, but it should not be taken on its own as an indicator of a catastrophic engine failure. I would not (don't myself anyhow) feel a need to keep the engine raced a little at a stop the way you describe.