Bit late to the party but a few random thoughts:
Dynamic Elongation(Duncan)
UIAA 101 and EN-892 are very similar, with all the tests being the same with a few extra bits added by UIAA 101. Dynamic elongation is defined in EN-892 section 4.4 Dynamic Elongation, "Where tested in accordance with 5.6, the dynamic elongation shall not exceed 40% during the first drop of each sample". 5.6 is the Drop test for determination of peak force, dynamic elongation and number of drops, shown here on this nice UIAA pictogram:
Dynamic elongation IS information that has to be supplied by the manufacturer, it is 37% for an iceline for reference.
Impact Force
Beal have ALWAYS had the lowest impact forces of any equivalent rope, the the extent that Michel Beal has had accusations leveled at him re his results. As yet, the secret to his magic sheath weave/application of fairy dust is unknown.
The bigger question is does the rope impact force matter? As petejh alluded to above, it depends! Petzl have actually done a load of good work on this to get some real world values for forces at the belayer, top piece and the climber.
A brief summary of what they found:
- Humans are a lot softer than a rigid mass - peak force at an anchor was 70% higher with a rigid falling mass than a person!
- Belay device makes more of a difference (Increase in forces) at higher fall factors* when comparing a grigri to a reverso.
- Rope drag makes a massive difference (and something MOST climbers forget/don't understand). The force on the climber remains constant but the more rope drag, the higher percentage of the force is felt at the top piece than the belayer - it reduces the length of rope that if absorbing the energy of the fall, effectively increasing "fall factor".
So would the rope impact force make a difference - yes
Would it matter for a 0.3 factor fall on a free running rope - no
Would it matter on a bigger fall on a winding route with moderate rope dag and the last piece being a rubbish rp...... I think so!
Now we've all decided that skinny halves with low impact forces are the way to go, we realise that only time ropes actually "fail" is when they are cut........ Now where's that Edelrid Protect catalogue?
*I hate "fall factor" but it seem to continue to be used and it gives most people an ideal of the severity of the fall so I have used it too, even if I can't forgive myself.