One aspect of "spin out" that almost no one mentions is the affect that a lull (diminishing wind) has on your fin.
Think about it.......
When you get all dialed in and you are comfortable with the amount of rear foot pressure you are putting on the fin, and the fin is working well, especially when heading as high as possible upwind, any change in the pressure on the rig results in an immediate change in pressure on the fin.
What often happens (to most of us I'll bet) is that as the rig pressure diminishes, we tend lean back, or sheet in (or both) as there is a significant change in the "pull" of the rig.
When we "fall back" and/or sheet in where does the pressure go?
Right down your back leg and onto the fin, which now "spins out" because you've increased the pressure on the fin, at the same time the rig pressure is diminishing.
I've found that even really super good fins still "spin out" occasionally, and most often it's when I sail into a lull in the wind speed.
You would think it's the other way around, but when the rig pressure increases, it pulls us more toward the lee side and actually lightens the load on the fin slightly.
Glad the sanding of the logo had a positive result.