I remember a few years back, when EI had 747s (and since they've long stopped operating, I hope I'm not breaching any confidentiality!), the airline used to operate them from Dublin to SNN, en route to the US. The acft were usually pretty light for this sector and the fuel burn for the sector was usually around 6t.
HOWEVER, due to the light takeoff weight, the aircraft would face a situation where its V1 was less than its VMCG and consequently, its fuel load was bumped up to a standard 25t, to deal with this.
On a purely academic point (though probably not, if you're experiencing it), it's surely illogical for the VR to be below the VMCG, because you'd effectively be saying that the speed at which the aircraft can safely lift off is less than the minimum control speed on the ground. The logic of the V1 not being below VMCG is that you can't have a decision speed which is less than the minimum speed you need to control the aircraft?