Well proportioned diamond?

Hello- I Am looking at a princess cut diamond that is a little over a carat, F in color, VS1 in clarity. In terms of cut and being well proportioned, it meets almost everything your book states: 65% table, crown angle-34.6%, crown height-12.8%Pavillion angle-46.8, pavillion depth-53.1, VG polish and good symmetry. However the only issue is the total depth percentage is 68.2%. Your book says disqualify anything over 65% for square cut diamonds. Is this diamond worth keeping? How much light would it refract? Thanks!