First let me say that I have only been here for two days (but have managed to read 90% of the posts) and have to say that I am impressed with this forum.
I disagreed on some minor issues such as the postings on the 12 wire branch ckt minimum, that insisted that a 12 wire minimum was the way to go with residential general lighting circuits, as I am of the opinion that most household plug ins are still wired with 16 gauge stranded, rated at 15 amps. Also, I am of the opinion, that damage caused by arc faults should be kept to a minimum in residential applications. Do a comparison test sometime by simply shorting out a 12 wire/ 20 amp ckt and you will find that not only is it more difficult to get a 20 amp ckt to trip but it also creates a lot more smoke (and sparks) in the process. By comparison a 14 wire/ 15 amp ckt using say a Square D Homeline breaker(quite popular here now) for instance will trip instantly and the spark itself is almost non existent. These are things I believe to have been scientifically engineered by our predecessors and not to be tampered with...
I must say also that I am aware of a "farmers threeway" as it was something my grandfather used in rare cases...
I have a comment on AFCIs... Local inspectors here are insisting they be used in bedrooms only to include overhead lighting and closet lighting on all aplications filed after Jan 1st. As these breakers are priced at $28.50 a piece here, this again would indicate to me a need to continue using a 14 wire/15 amp ckt for general lighting receptacles. This is not a problem for me as I have found lately that houses have gotten larger, bedrooms are considerably bigger now and require more receptacles, and more lighting, and I find myself pulling individual feeds into each individual bedroom, often times into two or three gang switch boxes... This is also a convenience for the homeowner, many of whom have repeatedly asked me, well which breaker do I shut off if I just want to shut off my bedroom? It also makes it easier to label ckts on panelboards... I have spent my share of time working with 12 wire in industrial applications so I have been exposed to this arguement before... and this is just an opinion... I'm going to post this and then I have one question for the knowlegable of which there appears to be many here...
