Yeah, I left that part out.
Higher temp = lower viscosity ("thinner") oil, so it will flow more easily, meaning if the pressure relief valve isn't working correctly (the spring is too short.. haven't taken the old one apart yet to check) more oil volume will bypass the circuit (than if the oil was thick/cold). Keep in mind that at a given RPM the oil pump delivers a constant rate of flow, and that volume won't be changed by viscosity nearly as much as a leaking relief valve would. Raise the rpms, and therefore raise the flow of oil from the pump, and the oil leaking through the bypass valve becomes a lower percentage of the total supplied by the pump, so you now have enough left over volume to keep the pressure up (despite the volume "leaking" past the valve) to keep the light from flickering and keep the CCTs pressurized.
That said, in this system, the light shutting off at 2300 doesn't mean the bearings/piston squirters/cams/etc are still getting the oil pressure (& therefore volume) that they were designed for at a given RPM.
For me, the $60 to buy the upgraded oil pressure relief valve was a total no-brainer. Thing is, as in CJ's case, it doesn't always help. For me, and many other people with this issue, it did.