If I’m honest, it didn’t help me pick a seat, just left me more confused, other than I’ll need a few to tune for different conditions.
What is a “soft” or a “stiff” kart? We use these terms all the time, but never see hard numbers on spring rates, resonance or damping, so how can you decide what you have? Then you have to consider the softest thing in the cornering system is probably your sidewalls.
You can’t go by tubing size or wall thickness alone because frame construction plays a role too, especially on diagonal load transfer (jack). Narrow waist, vs wide behave differently.
So where does that leave us. Confused I guess? Make sure there’s a seat in there, that’s a decent starting point.