So having taken delivery of a batch of the Edelrid TouchTec Viper ropes, it was time to test their mettle and see if the change in texture was significant enough to notice with the rope buzzing through your hand as you lower your partner off their climb.
For those who don't know Edelrid TouchTec is a safety feature where there is a visible and tactile difference in the rope on last 5 metres of each end; a black strip with a subtle 'spiky' feel. The idea being as you're lowering your partner to the ground there's little chance of you lowering them off the end of the rope, since you'll feel the change and know that the end is nigh before an accident.
This all said, does it work? In a highly scientific test Dick ran across the shop clutching one end of the rope, I closed my eyes at the rope ran through my device until I believed the texture had changed ...
The results? Each time Dick and I both caught the change within about 3" to 6" giving plenty of latitude for the five metres or so rope remaining and if you don't pick up on the first change of the texture it actually changes back again right near the very end of the rope, so you have two chances to keep your partner alive - very impressed!