Incorrect piston powering

A piston is getting powered by a not connected redstone block, although it shouldn't.

**What I expected to happen was...
Piston not getting powered

What actually happened was...
Piston extended

Steps to reproduce:
1. Place a block of redstone with 2 empty blocks beneath it
2. Place any piston underneath the redstone block
3. Update piston by placing any block on it's side
4. The piston gets powered and extends, although it should not

(update)
I have just been informed that this issue, is in fact, a duplicate (I swear, I have searched for it, guess I just didn't read through that one well enough). And since I cannot delete this report (or haven't found the button for it) here it goes: In my opinion the main issue is inconcistency. Pistons (and turns out other blocks) get powered from a source above them, but no below them or to the side of them. Also with the diagonals. Ones below are powered and ones above - are not.