I've no idea about all this IRATA stuff, but when I first started messing around with new routing and shunts I threaded a massive handle of 5mm through that wee hole...not the best plan with hindsight.
These days I just have a small finger and thumb's worth, but to go down a few moves I never use it, I just squeeze it open whilst doing a one arm lock. I'm sure this is totally cowboy, but I'm happy enough that its OK. Still, shuts have always given me the heebie jeebies, but I don't know of any other device thats so handy for working moves. Someone must be able to design something better, half of these petzl devices are fundamentally unchanged since the dawn of time.