No. AD in the good ol days served as a Damage reduction (based off def rating) whislt below 35% health and upon reaching 0% health healed the pally for 30% health, neither second wind or Ji'Kun's thingy will do much to save you don't get me wrong its an alright trinket, but its no AD. the heal just isn't big enough, and i get the feeling that the interply with second wind will lead to a lot of trinket proccing, but second wind would have covered you anyway., or trinket popped so second wind doesn't which kind a makes me not want to take the combination of the two.
You could, however, find argument FOR the trinket as saying "then I get the basic functionality of Second Wind in a trinket and I could pick up another talent"
Or... you could not care about second wind as a tank to begin with, and view the trinket as a nice little quality of life thing, and continue to stick with Enraged Regen for 95% of the encounters..... or am I the only one in that boat?
If you want to stick with ER that's your choice and what you do in the privacy of your on home is none of my business. Personally i'd rather have Second wind than the Trinket. Assuming boss hits are 1.5s and a 600k buffed health thats 18k HPS so by the time the boss's swing timer is up again i've had 2 ticks so 36k which is 90% of the healing of the trinket, I'm not gonna quibble over 4K if it means not having a CD on the heal. Not that i think either are gonna make a real difference in your survivability.
There's also the problem that Ji'kun's is an Expertise trinket. I don't like getting expertise from trinkets, firstly it means i lose a lot of flexibility so i can't change that slot without screwing over my connectivity i can't drop in double mastery trinkets for easy stuff or double stam trinkets for stuff that tests my EHP; And secondly if you look at the stam/secondary stat ratio for trinkets its about 1.33:1, whereas with gems the ratio jumps up to 1:1.33. I get more expertise per gem than i do stam, and i get more stam per trinket slot than i do expertise, so ideally i'll be trinketing stamina and gemming expertise.
Secondary functions of all 5.2 trinkets is weak imo, except for the valor trinket (and that only because of its frontloaded nature which I mentioned in my summary).
I now value the trinkets mostly on their static bonus, which means for me:
Soul Barrier > Talisman >= Fortitude - all others are not that great.
So I actually ended with sticking to my 489er mogu trash stam trinket paired with the talisman and I plan to replace the stam trinket with the soul barrier. LFR Barrier is too weak. Little more stamina for a less reliable use? Not for me.
So if you want to throw in the secondary functions of the trinkets into your decisionmaking, you should have a good plan ho to use the trinket, because they are all really not that strong.