Petzl Tibloc for the bottom rope grab on a 2:1 pulley system?

Has anyone tried using a Petzl Tibloc for the bottom rope grab on a 2:1 pulley system? Or does anyone have a good reason why that wouldn't work, or be worth the effort? I've used my handled ascender before, which worked just fine, but I'd prefer to lighten my 2:1 setup. I'm just looking for excuses to buy some new gear, and the new Tiblocs seem pretty neat.

To be clear, I want to replace the inverted ascender in the image below (credits to Pete Zabrok, aka Pass the Pitons Pete) with the new Petzl Tibloc (the one with the plastic bit to hold it to the rope).

I’ve heard complaints from people (I believe Mark Hudon, and also PTPP, but I could be misremembering that) that the tibloc does more damage to the sheath. I believe because the cam on a ‘true’ ascender is pinching the rope not just teeth in sheath, it’s weighting both the core (pinching motion) and the sheath (teeth biting it’s a lot gentler on the rope. Where the tibloc is getting almost all of it’s holding power from teeth in sheath.

Hopefully someone smarter, and more experienced (paging Hudon and PTPP) will be able to confirm, or completely blow my theory to shreds.

For a 2:1 to work well I find it needs everything to be perfect. As a system it is much less forgiving than a  3:1 or a counterbalanced haul. In part this is because you have to do so many more resets as the bags are only being lift a few inches between resets. I'm guessing that a tibloc will be slightly more difficult to reset, and hence be a bit of a pain. If you don't want to carry or buy a separate basic, just use one of your jugs?

I'm not dissatisfied with the efficiency of my 2:1 hauling setup, I thought a Tibloc might work and would be smaller and lighter than even a Petzl basic ascender. My ascenders are old and bulky and a pain to carry up lead pitches.

I couldn't bear not knowing if a Tibloc would or would not work well for a rope grab on a 2:1 pulley system, so I ordered one. Worst case scenario, I've got a new semi-useful toy and the knowledge that a Tibloc is ineffective in a 2:1 pulley system. Best case scenario, it works well in a 2:1 pulley system, and my hauling gear is even smaller and lighter! I'll update everyone when it arrives and I get a chance to try it out. Don't hold your breath, all two of you. ;)

Damn, I just wrote a big reply and then lost it. When I was soloing Iron Hawk I used to tribloc in the way you describe. Every now and then I’d hear this odd groan from the hauling system. I didn’t notice till later that the groan happened when the tribloc was slipping and shredding the sheath of my haul line. I wouldn’t recommend using it. 

Well shoot, now that you mention it Mark I think you've made note of that instance before somewhere online. Sadly, it's too late to cancel the order, so I guess I'll test the new Tibloc and see if it performs any differently than the old one. I've got some beater rope to test with and I'll just fill a haul bag with heavy stuff for the experiment. Unfortunately the only places I could experiment would all be free hanging hauls, so I won't get the same effect as hauling a huge load up slabs. Thanks for the heads up, though! That's what I get for being impatient!

I don't have one of the new ones, but this latest Gen if tibloc has a spring loaded plastic thing that pushes the carabiner into the rope, I'm thinking it will reduce the slippage / sheath damage from not engaging it properly.

If you took your time to make sure that the biner is really engaging the teeth into the rope it might be fine.
I have the older, larger Basic. If I had to buy my kit again, I’d get the smaller one and call it good. 

Duncan Domingue wrote: I'm not dissatisfied with the efficiency of my 2:1 hauling setup, I thought a Tibloc might work and would be smaller and lighter than even a Petzl basic ascender. My ascenders are old and bulky and a pain to carry up lead pitches.

If you dont carry jugs on lead, you will once you take a fall on overhanging rock.

Ha!  I was going to say no [without ever having tried it] because the Tibloc will knacker your haul line. But Mark Hugedong knows this as fact. So there. 

I use, but not frequently, a Tibloc as part of a pully system with a GriGri when top belaying.  Never had an issue perhaps because I use a carabiner that compresses the rope when loaded.  I've also used a Tibloc with wet/icy rope for crevasse rescue 2 or 3 times and have not had a problem.  Have never use a Tibloc with less that a 9.4mm dia rope, but suspect that skinny ropes might result in more slippage.