Concerning power foci, fluff or RAW? Options

[Laodicea]

There's some language in the description for power foci on SR4A, pg 200, which might be a little ambiguous.

Power foci are the most potent and treasured of all. Possession of a
power focus feeds a magician’s Magic directly, making her efforts more
powerful in all forms of magical ability. A power focus adds its Force
to all tests in which the magician’s Magic is included. A single power
focus can increase a magician’s ability to cast spells, call on and control
spirits, and bypass astral barriers. A power focus does not help in
Counterspelling a hostile spell as it is cast, nor can it duplicate the
unique ability of a weapon focus.

The first 2 sentences seem like they are probably just fluff. But maybe they're not. If they're taken as rules, and not fluff, does this mean that it actually raises the magicians magic attribute? Can the magician then cast higher force, up to their magic + power focus rating, without overcasting? This would certainly be powerful, and would indeed make them "the most potent and treasured of all."

Thoughts?