I have solved for me the FG tying problems. My problems were that holding the line in my teeth often didn't work as it would slip before i got the knot done, and the line coming from my mouth was hard to focus on. Using the tool pictured allows one to solve both problems.
1. Set up your rod so you can put the braid under tension, the usual start point. Set the length of braid coming to you right so you can keep tension on it with a slightly bent rod.
2. While seated, put the tie through a belt loop, then wrap the braid around it a number of times. It will stick to the tacky surface and not slip.
3. Tension the braid and tie your knot in front of you waist high on the braid coming from the rod to the tie.
4. Set the knot in the normal way, lots of force using the business end of the leader and the business end of the braid, not the tags.
5. Loosen the braid and make the finishing half hitches or whatever you finish the knot with.
This tool allow the weaves to be formed tightly enough that they don't slip at all when doing the very high force setting of the knot. They are perfectly aligned, no slipping from the teeth, no looking cross-eyed at the knot as you make the weaves. I use 20 weaves, all in succession without intermediate tightening. They are already tight when they are formed. Try it.
I don't usually tie them in the boat. If I break one, very rare indeed, I use another rod. They last so long and are so reliable that breaking one while fishing is not an issue, so I tie them in my pole barn before fishing.