Weapons vs features (collision detection and aoe)

[Erik]

I found that whenever a weapons aoe is smaller than a features model radius it will detonate on the outer edge but no deal any damage since (wild guess) it uses the center of the feature instead of the edge(which seems to be the case for units).
Is this a bug or a feature? (no pun intended, duh)

[Deadnight Warrior]

This is a well known fact that I've described a month ago.
And Kloot probably know about it even longer.
It's the way AoE system was implemented on features (aka flawed logic).