Quote. "but it's really useful to know if the wind component on the takeoff roll is significantly different to that you've used for your performance calculation."
I've never seen any SOP where this is a stated procedure nor is it likely to be reliable because of the update rate and the changing variables.
I've seen wind speeds of 100 kt and varying wildly whilst taxiing and seen the ground speed calculated to be anything between 5 and 20 kt while we were parked at the gate!
With the conservative values used for performance calculations and safety margins, I think one would notice any relevant change in the wind conditions especially when ATC say "Wind is xxx, you are cleared for take-off."