Has anyone actually chronographed the Remington loads with the 175gr Core Lokt?

Not recently, but there was an extensive list of chronographed factory load velocities in the Speer #8 manual. I don't have it in front of me, but as I recall, the 175 grain 7mm RM was pretty laconic.

Of course that only pertains to one lot of a particular factory load out of a single rifle. Other lots and other barrels will yield differing results. However, it is true that the 7mm RM, along with the .243 Winchester, is infamous for being underloaded by the factories (more so than most calibers, anyway).