Here's my post from that thread. I start with a length and build my arrow from there.

Everyone may want their arrows to be cut different. I shoot a 28" draw and have cut my arrows 27.5" for years. When I build an arrow I choose spine, etc, based on that finished length.

While you can add length, it is not necessary unless it makes you feel more comfy.

Things to remember when building a set of arrows are:
1. make sure all parts, inserts, nocks, etc, are installed properly and are straight
2. Proper spine
3. Proper FOC
4. The best fletching that works for you. Don't be afraid to experiment during off season. I do every year.

Dan