So, I've been incorporating the 'Illustrious 18' deviations into my gameplay.

Just out of curiosity, I plugged each of the 18 individual deviations into the CVCX 'Index Chart Viewer' on the website card-counting.com. This online index chart is pre-set with 6 decks, S17,DAS, LS.

I also compared the illustrious 18 with the index's in Wong's "Professional Blackjack" Table A4. This table is for 4 Decks, S17, DAS.

The indexes found in the 'Illustrious 18', the 'Index Chart Viewer', and in Wong's Table A4 are usually the same, but there are different index numbers for 6 of the 18 plays:

TT v 6: (4) (5) (4)
12 v 2: (3) (4) (3)
9 v 7: (3) (4) (3)
16 v 9: (5) (4) (5)
12 v 5: (-2) (-1) (-1)
13 v 3: (-2) (-2) (-1)

Where the index number inside the first bracket is from the 'Illustrious 18', the second is from the 'Index Chart Viewer', and the third is from Wong's Table A4.

So, from reading Blackjack Attack, my understanding is that Don's indexes are based on a 4 deck shoe; whereas Norm's CVData online viewer states it is based on 6 decks. Wong's Table A4 is base on 4 Decks. The CVData online viewer and Wong's Table A4 are both pre-set to S17 rule. I'm not sure which soft-17 rule was used in the Illustrious 18.

All three of these information sources are beyond reproach and I have no doubts about their accuracy. Its just that I've become a little obsessed with card-counting this month and wondering what accounts for the slight different in these indexes.

Thanks for any feedback offered.

Cheers