But what is the point of knowing the crosswind component?
Far more important is to know the wind strength and direction as well as the gust factor.
To me windshear is far more hazardous than knowing the crosswind component is 17 kts instead of 15 kts?
A demonstrated crosswind is just that! It's a guide for the average pilot.
If your better than average you will cope with more if your less you won't manage that limit anyway.
It's the big picture of handling something which is inconsistent near the ground and that is winds.
Anyway the last thing you want to be doing in strong winds is fiddling around doing mental calculations to arrive at a pointless figure but instead put all your concentration into flying the plane!
Pace