What does third point in spinal tap do?

[Nabzy]

From reading the description of our in-stealth LMB, it looks like putting in the third point in our left tree only REMOVES defense pen and does nothing else. What's that third skill point do? I've seen some assassin PvPers talk about speccing that third point. 

 

Edit: I just looked at it on BnStree. It looks like it removes the stance change and lets you remain in stealth? Is that right?

 

[Shadovvv]

Tier 3 keeps you in stealth. The thing about losing defense/deflect penetration is most likely a typo.

[Nabzy]

4 hours ago, Shadovvv said:

Tier 3 keeps you in stealth. The thing about losing defense/deflect penetration is most likely a typo.

When you put that third point in, it crosses out Defense/Deflect pen as if you lose it when you put the point in. It still penetrates defense?

[ketiax]

On 7/1/2016 at 8:51 AM, Nabzy said:

When you put that third point in, it crosses out Defense/Deflect pen as if you lose it when you put the point in. It still penetrates defense?

No, it doesn't. After multiple testing I concluded that it's not a type, and when you take the 3rd point Spinal Tap can be blocked, parried, or resisted, in exchange for you being able to stay invisible for the rest of your stealth duration.