Does HCA score matter with AGS 0 cut?

[bqnbqn]

This was briefly addressed in another thread but I wanted focus on just this issue. I have seen comments where folks say the HCA score does not apply to AGS0 cut diamonds while others swear not to consider stones with less than a 2.0 HCA score. The diamond I'm considering buying is a AGS 0 cut H&A but has an HCA score of 3.0. Would appreciate any opinions on whether this score really makes a difference on this particular stone:

http://www.agslab.com/pdf_sync_reports/104071002017-PLDQR.PDF

Thanks for your feedback.

 

[Megenoita]

From GoodoldGold, which is truly the best site on the web for diamond education (I'm not affiliated with them in any way, just a fan):

Strengths

An Excellent HCA score (0-2) = an excellent reflector image.
An Excellent HCA score (0-2) = a diamond with minimal to no leakage via a reflector analysis, hence ...
The HCA offers a critical exam of what angle combinations produce leakage in diamonds (particularly under the table). Diamonds termed as "steep/deeps" (steep crown angles combined with steep pavilion angles produce light leakage in diamonds which the HCA easily and accurately identifies).
Many diamonds with excellent reflector images are good looking stones.
The HCA favors non-AGS Ideal/ GIA Ex shallow angled diamonds which in many instances are very bright and fiery diamonds.
Excellent for determining diamond appearance in spot lighting environments (fire) even if the diamond suffers in brightness.
It's free!
Limitations

Not all seemingly good reflector images = the most beautiful diamond.
The HCA favors shallow angled diamonds while there are many proportion combinations it rewards that lack brightness.
While the HCA does a great job of critically determining the presence of leakage under the table, there are many instances where this leakage is not visible or perceptible to human vision.
Nature of scintillation not determined (broad flash vs pin flash).
The HCA score can change (dramatically sometimes) depending on the scanner and/or Lab Report you are garnering the numbers from.
The HCA predicts light performance and is not a live analysis.
The HCA arrives at its conclusion based on the average measurements of only 17 out of 57 facets. Minor facets measurements on the lower girdles, upper girdles and stars (40 of 57 facets) impact diamond appearance and could sway a persons decision one way or another and even affect a final cut grade from GIA or AGS.
The HCA does not take into account painting and digging (minor facet cutting which disqualify stones from getting AGS Ideal or GIA Excellent rating/status).
The HCA does not take into account the variances which the major facets are cut to or meet point faceting. (Ie. Traditional symmetry grading) How close or wide the variances are determine the precision to which a diamond has been cut.
The HCA does not take into account craftsmanship (ie. optical symmetry) but presumes it when in fact less than 1% of diamonds cut in the world have it.
When regarding diamond "Spread" (the face up appearance of size) the HCA is intolerable to what most in the industry feel is just fine including the most conservative labs.

If you go to the site, it's under Technologies, then "A Consumer's Guide to the HCA".

In short, the HCA is not a live analysis, whereas the ASET effectively is. So when they seem to conflict, the ASET is always right.