Thanks, guys.

Dave55,
Yes, multiwire ckts present problems for those who don't recognize them, and I usually avoid them in residential installations. However, I use them on occasion, and have been wondering about the wisdom of doing so with the possibility of wider application of AFCIs.

Jps1006,

I have read several articles (maybe opinions?) in trade magazine, and possibly on this or other websites that as AFCIs become more acceptable, their application will be more widespread than just bedrooms.
In anticipation of this, would it be wise to avoid multi-wire ckts?