I apologize for 'putting words in your mouth.' The impression I'd gotten is that most supporters of the FET consider the idea of a spherical Earth ludicrous.
To what first-hand evidence do you refer?
The direct, immediate sensorial evidence that the Earth is flat.
Yet if Earth is spherical, and causes an immense spacial displacement (gravity), one would feel, at any point on Earth, that one is being forced "down," or, in the case of a spherical planet, inwards. Earth's immense size would account for the feeling of being forced downward. You could only be susceptible to gravitational curvature on a body significantly smaller, but with a similar mass.