This document was published in Jan 2002. You took quite sometime to find it. Anyway now that you have it will give you good insight into what's it all about.
The lift-off speed, VLOF, is limited by the tire speed (Vtire). As a result, V2 is
limited to a maximum value. Any V2/VS increase is then equivalent to a VS reduction,
since V2 is assumed to be fixed, and thus the tire speed limited takeoff weight is
reduced.
He is talking about increasing V2/Vs ratio. Since V2 is limited to a maximum value so cannot be increased so in a way fixed at max value and the increase in the ratio can only be affected by reducing Vs.