If I recall the UCI thing riders were beginning to take them off at events where they saw streamlining helpful.. like lycra.. the helmet manufacturers who like the slackwearr manufacturers relied on the moto is fast myth got the UCI to ban the practise although doing so neither reduce the strength or performance of the helmet and as most downhillers use goggles the little mud flicked up as roost is a negligable issue…
on the other hand way back in motox times JT one of the originators of the moto cool myth designed a clip on peak extension that was transparent aiding vision, after a spate of faceplant accidents it was found on crashing the flimsy attachment pivotted into the face slicing the nose off.. they were banned by the AMA and ACU as were any properly secured peaks. Riders reverted to duck taping old goggle lenses to the ends of their peaks to perform the same function
I have had two gyro flexi peak helmets including a xen which display this habit and now for any riding where a earth impact is routine / likely i have a Protec Ace Dig which has a screwed on peak on a hard poly shell potty helmet
