QUOTE (Mardrax @ May 11 2011, 01:12 PM)

Ehrm. Isn't the bonus for targets that are astrally perceiving? Not Assensing? How does this debate matter? I can perceive astrally without Assensing as much as I can perceive normally without Perception.
Well... Lets go to the relevant Books...
QUOTE (SR4A, Astral Perception)
While astral perception allows an Awakened character to sense the astral plane, actually interpreting what is sensed takes practice. Interpreting auras to gain information about the person or thing to whom they belong is called Assensing. A magician who wishes to learn more about an aura must make an Assensing + Intuition test, with the number of hits determining how much the magician learns, as outlined on the Assensing Table (at right). Without attempting to read an aura, a magician can still get an impression of what type of aura it is (spell, spirit, living creature, etc).
QUOTE (Noticing Magic)
Noticing if someone is using a magical skill requires a Perception Test (p. 135) with a threshold equal to 6 minus the magic’s Force. More powerful magic is easier to spot with the gathered mana normally appearing as a disturbance or glowing aura in the air around the caster. The gamemaster should apply additional modifers as appropriate, or if the perceiver is Awakened themselves (+2 dice), astrally perceiving (+2 dice), or if a shamanic mask is evident (+2 dice).
So, After actually looking up the relevant text in the books, in the end, there are a FEW areas where a Mundane can obtain the benefit of Astral Perception so as to gain the +2 bonus. It is a highly unlikely set of circumstances that are generally up to the GM for them to come into play. Most mundanes are not going to be using Shade, as it forces them to Astrally Project. Shallows and Riufts are so rare as to be a moot point. As for Tempo, I do not know enough about the drug yet (we are currently in the campaign, and I have yet to read the actual book, as I am a player) to comment one way or the other.
However, In the end, I still hold to may comments. See Highlights in the text above.
Magicians are the only ones who can interpret an aura (for the most basic of information) without using Assensing to clarify. Mundanes just do not have the knowledge to do so.