i have always seen nylon and polyester fibres quoted with the same approximate melting point, and load reduction point. The Art of knotting and splicing shows this to be @480 for each, strength fading @350. On page 13 of the excellent Samson Arborist Rope Manual, they used to send out, but now is available @:
http://www.samsonrope.com/catalogs/pdf/ARBORIST.PDF they say about the same. i think it is that dang Polyolefin stuff in some of the cheaper lines (ArborPlex, ArborPlus etc.) is what ya have to watch out for heat, strength wise; melting @320, fading at 200. Though it makes lighter rope, i think it is heavier per working capacity.
Slowing down is probably best in any case, but for speed demons a fig. 8 with gloves might be right. Seeing as a "Friction Saver", reduces the total friction at the anchor point; it will put more friction on the friction hitch, hence more heat. Because per a given load it will take a specific matching brake force to support the load, so if that braking friction is not at the anchor holding ya, it would be in the knot in a standard setup for climber. Often as increased, broken up friction (allows heat to dissipate some between friction points), i let the length of the line run between my feet, and around one. So i am taking some of the friction of my knot. This also kinda keeps a sense of there being more line below me, as well locking them on the line and moving knot down a lil'more makes for some unique leaning angle supports for me for touching things up.
Hey, i work in that position sometimes, playing on if my legs are drawn up, i have more leveraged weight in my chest so can roll upside down, extending them reverses. Kinda makes the hand saw wanna slip out though! Really like the new icon RB-Tree!
Blue Streak/ Gold Streak curiously are 2 ropes that a 16 strand eye splice is rated at 80% efficiency i think, putting it very close to a double bowline i think.
