I'm not changing the conditions with my questions. You're the one putting doubt on using your eyes to make measurements, which is ironic considering that that's all FET has.
I'd say this would go a lot better if we had something else in the water for reference. Ships, buoys, etc. Something hidden behind the horizon will become visible once it expands out with increased elevation.
But I suppose the OP is trying to make a different point? Do any FEers still even hold to bendy light?