So, SR4A dropped the section in the description of each foci that stated that the dice the foci provide can be withheld for drain, making me assume that in SR4A you couldn't use foci dice for drain (with the exception of the dice provided by Centering Foci). But rereading a completely different section of SR4A today, I noticed this section:
Pg: 185 SR4A: Ritual Spellcasting
Ritual Drain
At the end of the ritual, each member of the ritual team—including
the spotter—must resist the Drain of the spell. Individual magicians
with foci or bound spirits not otherwise occupied may use them to
help with Drain.
Does this mean that foci can assist all drain tests (depending on foci type) and that they forget to write it into the foci section? Or does it mean that you can only use foci dice to assist with drain while ritual spellcasting?