I'm not an expert, but I would advise against cutting them arbitrarily.
Personally, this is how I tune wood shafts:
Install point on bare shaft, and shoot a full length shaft. Hopefully it shoots week. Remove point, cut shaft 1/4", reinstall, repeat until shaft shoots straight, as if it was fletched. In other words, I try to get my arrows to fly perfect at 20 yards as bare shafts before I add fletching.
You can do this for every shaft, or just two, and cut the rest to match, depending on how precise you want to be.