The Vesco liner is a bad comparison between the speeds at El Mirage and Bonneville.
Most liners benefit substantially from the additional distance to run up.
The "Slide Car " minimums were established by the first person to get a season championship under those rules he made himself.
After the submission by him and no evaluation by the board he came back to even lower those and that is when they took a look and wisely said "NO" but the first cats were out of the bag so to speak.
They are chasing each others tail and you are not in the inner circle.
That is what you are competing against.