An "aura" / spheric / personnal mana barrier sustained by said mage will provide the same without the problem of line of sight. In fact it could be better because it could go over 6 as it would match the net hits of the casting up to the force.
Couldn't this cause an issue with other mages tracking the astral connection back to the caster?
-Erich
Yes, the connection can be tracked
It also is going to call in all the site's magical responses as your barrier has to force its way through any wards in the building.
The question was not if you will be stealthy but if you can find a way to have a kind of armor against spells. As said in another post, if you enter a building with a milspec armor and no autorisation, you will have same issues (not magical but physical).
In a mercenary setting or where subtility is not an issue it could be great.
I can see a few more advantages for something like this. let's say you have a man spirit cast this kind of spell upon you, no one can tell at first glance if you are awakened or not (except following the link to your spirit and comeback to you). You still have counterspelling. You could avoid or delay the acquisition of masking and extended masking meta. It will prevent assensing on you but not yours upon others.
