You evil genius......lol. I didn't think about that. Well Seem both Litany and Shield Wall might be doomed to be one of the least use skills in our toolbox if something isn't done to help these buttons (specially in higher tiers) not be so suicidal and prone to abuse by players.
Least used doesn't mean useless. They have amazing niches where these skills, when covered for their weaknesses, can excel.
Hiddenhoard T5 with a Guardian and a Brawler tanking, last phase tanking, Guardian uses Litany, Brawler uses One for All, both gain a significant damage reduction they share and can have free reign for the next 15 seconds.
(there was a video of how stupidly strong this combo can be with a Guardian and Brawler not taking damage at all for the duration when executed properly)
Just the other day I join a t5 Apothecary, the leader a bear healer, was trying to get better gear for it but kept dying. So I stupidly decide to try Shield Wall on him to help him out and ended up dead. On the 2nd attempted I said to myself, well this time Ill use Warriors Heart to mitigate the damage from the yellow eye (morale drain attack) and it worked but because the attacked happened more frequently then the cd on Warriors Heart he die again. I asked about his mits and of course not were they should of been on t5. I write all this to point out that Shield Wall in it's current form has had very, very limited use.
In your example, Shield-wall coupled with Redirect should easily be able to save an ally from the Eye given by Karsija in T5, unless you're both significantly undergeared. This is further enchanced CAB.
I've Shield-walled glass-cannon RKs in that instance, took around 1m damage when timed with CAB and Redirect and instantly recuperated the damage back.
Point being, you're not supposed to keep Shield-wall on, but use it to mitigate a predictable damage spike on an ally, while using your own damage reduction to reduce the damage (and quickly recover from it)
And as I've mention before on other threads having to use 1 emergency skill to save you from another emergency skill is in my mind completely absurd. I could be wrong (<--sarcasm) but my idea of an emergency skill is to get you out of a jam not to put or keep you in one. And then having to use another emergency skill to save you from the 1st one is, well......
Neither Litany nor Shield-wall are self-emergency skills, but they're intended for group or an ally and as such, have draw-backs.
We have parity with similar skills, Litany being near equal to In Harms Way and Shield-wall being near equal to Sacrifice, with both having massive penalties if you mess up, but if executed properly with timing can be attempt savers.
So...I ask, what's the point of this discussion?