I'm familiar with the idea of using 6-7mm cord as a tag line but has anyone any experience abbing on it directly? Only asking as I saw that Steck carried 60m with him on the Peuterey Integrale to do the abs with.
Be careful with differential rope slippage, slashing thin ropes and rope stretch.
Ideally practice with a top rope first.
Getting the ideal amount of friction takes practice.
If possible I put both ropes thro the same hole in the plate and if the rope is very thin an additional friction hitch after or before the plate.
On a 20m free ab on the double 5mm, an in line Italian hitch and ATC worked very well, but otherwise felt on the limit of acceptability for safety, not for the faint hearted. I still prefer double 10mm.
I use a 6mm line as an escape rope for soloing on relatively easy alpine routes, and I've used it a couple times with no issue abbing with just the ATC. But that was on low-angled ground where most of my weight was still on my feet.
How does the in line munter work? Do you extend one on a sling or something? Does it matter what order you use them?