I don't know if this has been addressed already.
As I was testing smoke bomb nano on medusa grandmatriarchs earlier today I noticed something I didn't like.
If you cast smoke bomb while being rooted (Burden of Atlas) the sneak will only last for as long as the animation.
As soon as it's over you get snapped out of sneak by the root active in your ncu, through no fault of your own.
Concealment is not an issue here as my shade has 3k conc and I was able to sneak on the mob unnoticed in the first place.
Now I might have been able to deroot myself before casting SB (maybe), but that would defeat the purpose of this nano since I understand it was meant to be used in case of emergency.
Had it been a serious boss or pvp I would have been smelling the reclaim daisies.
This would easily be solved by making SB purge your ncu of root nanos or something to that effect.
And another thing:
if you cast SB while a perk action is being executed you will be brought out of sneak upon the termination of that perk action.
Since shades have a lot of perk action with long execution times and usually several active at the same time it means having to wait for several seconds before it is safe to cast SB.
Again this, in my opinion, defeats the purpose since in emergencies seconds are precious in deed.
This could also be remedied by having SB end the execution of all perk action immediately.