Instead of the knot, get look into getting a decent ascender. The rope you are looking for is called dynamic rope (it will strectch up to about 25%). Check this link for a bunch of info:


http://www.huntingnet.com/forum/tm.aspx?m=1307404&mpage=5&key=pretzl&# 1312475

http://www.huntingnet.com/forum/tm.aspx?m=1309286&mpage=2&key=ascender&amp ;#1316325

I promise you we will be reading about somebody falling again this year. Be careful and protect yourself from the time your feet leave the ground.