It seems Yasuo's shield is a long time questionable issue when it comes down to "hitting his shield should grant a kill or assist.".
At the moment; it does not.
I've found posts about this shield from 4 years ago.
I've found posts about this shield from 10 months ago.
They have upvotes, and it seems most people just want clarity
Personally, I'm used to it. But the question is: Does it need bug-fixing?
Let's see which problems occur:
Towerdive. He dives you, you hit only his shield, he kills you, turret kills him, executed.
Teamfight. You hit only his shield, ally kills him, you get no assist.
To me, it seems passively abusive to reduce enemy gold in some way.
More about shields and why Yasuo should be changed:
**Quoted in season 3 patch**
"Champions that waste basic attacks or abilities on damage nullifying shields or absorption shields without breaking the shield (Kayle's Intervention, Poppy's Diplomatic Immunity, Morgana's Black Shield, Barrier, etc) will now be properly granted assists if that champion dies within the appropriate time frame"
I am aware that Yasuo's shield interacts differently. And the shield acts more like as it's own individual. But it doesn't beat the fact that you did something! Assisting after all, should grant an assist. Hell, even Akali (W) gives assist! (It used not to)
Yasuo shield needs updating and we shouldn't beat around the bush anymore.
If I'm wrong, then update the tool-tip for newer players.
Clarity is important.