per Ezelius:
The European death knot (EDK), i.e. the offset overhand bend, has the advantage to slip over edges
Any end-to-end joining knot that is
offset will translate more easily around an edge...particularly a 90 degree edge from low anchors.
The term 'offset' is defined by a particular geometry where the knot core is displaced from the
axis-of-tension.
I have not tried the Reever knot on climbing ropes for rappel
This is fortunate because the Reever knot ('bend') is not inherently secure. Once disturbed, it becomes insecure and cyclic loading will trigger failure. Disturbance of the core of the Reever can come from contact with rock edges/protuberances...
I think figure eight bend, Reever bend and double Fisherman's knot are a knots for joining two climbing ropes, if one does not have to consider sliding the rope over sharp edges where it can get caught.
The primary consideration in life critical applications is security and stability.
In situations where it is known that an end-to-end joining must translate around an edge (particularly from low anchors), an offset structure should be used. Depending on the current environmental conditions and rope type (eg snow/ice/water/mud/stiff ropes/very slick ropes etc) #1410 offset overhand bend may require additional maneuvers to increase security.
According to Wright Magowan (Alpine Journal nr 40 maj 1928, Knots for Climbers) the Reever knot is reliable and strong. It reaches 86,4% of the cord strength.
Strength is irrelevant.
What matters in modern textile ropes is security and stability.
The Reever knot/bend is not
inherently secure and should not be used in life critical applications.
I have confirmed its vulnerability by joining a Beal 'Joker' to an Edelrid 'Corbie' rope (both EN892 certified dynamic ropes) - and once disturbed by an edge or protuberance, cyclic loading acted to cause a loss of security - and the ropes slipped apart.
In the real world of mountains/rock surfaces, it is almost guaranteed that there will be edges and protuberances... rather than a perfectly uniform/smooth surface. Also, if abseiling - there will be some movement of the (joined) ropes as the abseiler descends - including some cyclic loading (induced by stopping and starting or uneven control of descent).
NOTE: There appears to be a strong focus on
strength - as a crucial determinant for placing reliance on a joining knot in life critical applications. In fact, the notional concept of 'strength' is irrelevant. The crucial determinants are security and stability.
Ropes are also probably different now than for 100 years ago.
No 'probably' at all.
It is 100% confirmed that modern climbing ropes are completely different to the ropes used in Wright/Magowan era!
You may not be aware of the EN892 standard (dynamic ropes)?
And EN1891 standard (low stretch ropes)?
Modern climbing ropes cannot be sold on the market unless they conform to an ISO member nations standard.
Also, no climber will purchase a rope that doesn't carry a certification compliance mark.
In the Euro zone,
CE marking for class 3
PPE is compulsory.
The new PPE regulation 2016 (Euro) has closed many loopholes - and conformity to EN1891 / EN892 is mandatory as part of that
CE regulation.
In the time of Wright/Magowan, CE regulations and EN standards for mountaineering ropes did not exist.
Furthermore, modern climbing ropes are
synthetic, not vegetable fibre!
EDIT NOTE: Typo's corrected (eg "ad" edited to
and... "clipped" edited to
slipped)