Setting a fixed rail pressure will cause a loss in dynamic fuel range. If the system is truly set up as a closed loop pressure sensing control, why not make it follow(or better yet expand) the pressure changes of a real regulator?
I see no benefit of keeping fuel in the engine compartment any longer than it needs to be there. Most generic fuel rails hold a large amount of fuel. If hot fuel is bad(is it???) then, would this style system not make the heat at the injector worse? who cares if the fuel tank gets warm really? Example... I wouldn't want to limit the water flow out of my engine to keep my radiator cool. The goal is to keep the engine cool. Targeting the radiator temp is not the goal. Seems to me that the same would apply to the fuel system.
Not sure about the XFI, but the Holley system can be configured directly to control a ssr to drive the fuel pump with pressure feedback/ map control if you wanted or needed to do that sort of system.

I am obviously against this setup, but it does offer some interesting abilities/tricks that may be beneficial in some applications.