It’s pretty straight forward. While fighting Lagon he uses a breath attack that you should avoid. If he corners you with it, logically, with this talent you might think that dashing through it works. You are after all invulnerable. You will still die through his breath while Shifting. Talent is not working at all on that fight.
Yup. Friend playing rogue just encountered this on Lagon in Echoes.
Literally just happened to me too. Not sure if working as intended.
RIP HC, had to google real quick to see if i was insane but i guess it really is just bugged on Lagon then. Goodbye crafting mats 
Yeah, I think is not working as intended, also have that problem in Lagon, but many times I felt I was hit while shifting as if I didn’t have the talent. didn’t try it on the soulfire boss with the enclosing ring, is a great way to tell if it works or not.