What''s wrong with this diamond?

[Firelance]

I''ve already choose a diamond but I was curious about this one:

http://www.jamesallen.com/diamonds/F-VS2-Ideal-Cut-Round-Diamond-1067887.asp

This diamond has a HCA score of .5 and returns excellent on all traits. But it falls outside of AGS and GIA ratings and I was told in another thread that it was too shallow. I was curious what was the reason for that?

 

[Garry H (Cut Nut)]

The stone shows some darkening in the photo and signs of a little painting which effectively lowers the crown / pavilion angle a little more.
Spread is great.
It would not be my choice for a ring, but would make a superb pendant

 

[Firelance]

Interesting, thanks for the comments. Impressed to see the man himself weighing in .