I believe there is a major flaw with the 'logic' of this method.
The tide level is being used as an assumed straight-line [base] reference to show that there exists concave curvature of the surface of the earth --- which then means that the reference line is curved and not straight --- which invalidates the alignment of the individual sections of the 'survey'.
The tide level is being used as an assumed straight-line [base] reference to show that there exists concave curvature of the surface of the earth --- which then means that the reference line is curved and not straight --- which invalidates the alignment of the individual sections of the 'survey'.