So I'm out in the shop and working on 8 builds, which I'm sure will put me over 100, and wondering "why all the conversation about neck angle"? I see folks post about a 2 or 3 degree neck angle and ask myself, "Why bother?". We're not talking about an Eddie Van Halen "shredder" here. I start with a rift-sawn piece of hard maple and check that it is completely flat on my saw table, plane it down to 7/8 inch, shape it, and when I'm done its a completely flat neck. I set the action at 2/64 at the first fret and 6/64 at the 17th fret. I think this is a good compromise for both finger and slide style of play, but some of my customers even set the action a little higher to suit their preference/style. Fret buzz or action has never been a problem. So why on earth would I care anything about neck angle on a neck that doesn't even have a truss rod and is attached to a cigar box? Am I missing something?
Angling the neck eliminates the need for string trees, which is almost universal on flat-neck builds. It is, of course, a lot more time-consuming and tricky to do them, but the professionalism and beauty of them takes your CBG to a whole new level! Just an opinion ... :)
On 6+ strings it is done mostly because the neck will bow from string tension. Whether or not 3 strings will bow a quartersawn neck over time, I don't know. If the action of your gits is staying the same over a long period of time then I wouldn't worry about it. The Kid's explanation of string pressure on the bridge makes sense though.
Thanks for the input guys. "Kid" your answer makes a lot of sense and I can see where in an acoustic instrument this would be a factor.