In my application I would not bother pinning it,I'm not a drag racer though,and I can't use a fluidamper with my belt driven LP anyway.
I did install my darn dampener and forgot to tighten it the rest of the way down,well the bolts backed out a little,I tried to tighten them while waiting for a ferry @ Nanimo,stripped 3 bolts,So I found a pop can in the garbage,made a shim to make the dampener run fairly true,tightened the hell out of one bolt,made sure not to jurk the RPM around and made it the 300miles back home.
(One of the times I was nearly in tears in my adult life)

what are the benefits of the fluid amper, and how nessicary do you believe it really is?

With age the stock damper has a rubber strip or ring around it,with age it will dry rot or crack.

The fluid damper balances out the torsional vibrations.

Torsional vibration is a concern in the crankshafts of internal combustion engines because of several factors.

Alternating torques are generated by the slider-crank mechanism of the crankshaft, connecting rod, and piston.
The motion of the piston mass and connecting rod mass generate alternating torques often referred to as "inertia" torques
The cylinder pressure due to combustion is not constant through the combustion cycle.
The slider-crank mechanism does not output a smooth torque even if the pressure is constant (e.g., at top dead centre there is no torque generated)
Engines with several cylinders can have very flexible crankshafts due to their long length.
There is inherently little damping in a crankshaft to reduce the vibration