Probably because it increases the chance of the piece pulling. But if you’re climbing some splitter crack with solid placements, I wouldn't lose sleep over it.

Anyway there is something more important than your belay device. Although less controllable in multi-pitch climbing, how hard of a catch your belay gives is much more important than the choice of belay devices.

The impact force is partly a function of the belay device; especially so on a multi-pitch climb. In particular, if the climber takes a factor-2 fall, there is nothing the belayer can do to reduce the impact force (except, I suppose, let go!). Assuming the belayer holds the fall, the impact force will largely be determined by what belay device is being used.

Jay

I've never used a Trango Cinch, but would the slippage of the Cinch help to alleviate some of this issue? How much does the Cinch actually reduce impact force at high fall factors?

in theory a rap has to dissipate more energy than a lower

More like one of the best possible belay devices to use on a multipitch climb. It’s one of very few devices that can effectively hold a reasonably long factor two fall. Not to say that it can’t be done with an ATC and gloves, just that if your belayer is not wearing gloves, using an ATC, and you take big air onto the belay station, things won’t be pretty.

And what theory would that be? Is this theory one that you came up with on your own? Maybe you are suggesting that you a likely to be carrying more gear while rapping, increasing mass, and thus more (potential) energy?

+1

also, one of bit drawbacks with a Gri-Gri is that you need to completely disengage it from the carabiner in order to thread a rope. One must be extremely careful not to drop it. And imagine that thing drop on multi-pitch routes in crowded places like the Gunks!

Are you aware that Petzl explicitly states that the grigri is not to be used for traditional climbing?

Jay

Yes. I choose to regard that statement the same way I regard their statement about appropriate rope diameters.

People get dropped with inappropriate rope diameters.

Jay

People get dropped with appropriate rope diameters.

The relative risk of getting dropped using an inappropriate diameter rope versus an appropriate diameter rope, adjusted for potentially confounding factors, such as the belayer's skill level, age of the rope, and the condition of the Grigri, is almost surely much greater than 1.

Better?

Jay

Navy - hey, just a sanity check as this is completely erroneous and lately bordering on urban legend at times. There isn't a fall a competent belayer can't hold with a hip belay let alone an ATC - no gloves required. I've held lead falls directly onto me with both a hip belay and an ATC and while both were fairly brutal, neither was problem from a belaying perspective - no slipping, no burns. And no, it was the right thing to be doing as in both cases the anchor was dubious enough to not want to clip it and instead rely on stance and body cushioning.

Is it recommended? No. But do you need a grigri? Absolutely not. In fact, the only time mine sees the light of day is for solo aid.

I'll accept any accident in which the climber decked solely as a result of an inappropriate rope diameter...

People get dropped with inappropriate rope diameters.

Jay

You've caught an FF2 with a hip belay? Huh?

He's talking about at the belay device itself, and he's right. The total work done is the same, but when lowering it is split up between the rings and the belay device...when rapping, it's all on the device.

the wear on the rope will be the same or less on rap vs a lower ... rapping has one moving piece on the rope, the device ... a lower has two or more, the device, the top biner and potentially the rock

note that on dual strand raps, the load is split between both strands ... on a lower it's always on a single strand

Not to nitpick too much, and I couldn't give you a number, but there is a significant reduction in force on the device while lowering vs rapping because of the resistance of the rope running over the rings.

Pros:
-easier ratchet in a hauling setup should your second need rescuing,
-easier to pull in rope as compared to ATC or Reverso in guide mode.
-some safety benefit for leader if belayer loses conciousness.

Cons:
-Heavier and more costly than similar autolocking/autoblocking setup i.e. Reverso or Cinch.
-easier to drop than tube style devices.
-more advanced rappel or self lower setup than a common double rope rappel.
-higher force in falls, partially dependent on fall factor and belayer.
-can't belay two seconds as in a double rope setup without added complication.

Not an all inclusive list. Personally, I feel the pros are outweighed by the cons.

Let me make this simple for you.

Con:
Has the potential to produce a high enough impact force to cause your belay anchor to fail, and thus kill you along with your partners.

How can any list of "pros" outweigh that?

Jay