A high flow pump running at full output all the time, especially against a dead head regulator generates a lot of heat.
We're not talking about dead head regulators. The ones in question are return style regulators mounted near the tank so you have a "returnless" fuel line feeding the engine bay.
Actually, it is you who is talking about return style regulators mounted near the tank. The OP asked about deadhead or returnless systems versus return style systems.
The return regulators near the tank with a deadhead line to the engine compartment are nice, but it is still much better to use PWM to control and match the power to the pump to engine demand in any of these systems.
