Are EGL proportions reliable for use in HCA?

[thisisjohnny]

All things considered, how reliable are low HCA scores on EGL diamonds?

 

[Garry H (Cut Nut)]

Often EGL labs (which have different owners in different places) use %'s for crown and pavilion rather than angles and %'s are not as accurate as the angles (all be it rounded) data used by GIA and many other labs.
EGL as a low cost operation is also more likely to use less expensive less accurate non contact scanners.