Thanks again.
"The fewer decks in the game one plays, the more playing indices one should use."
Agree as more extreme true counts are possible.
"The authors mostly agree (we will await for T-Hopper's dissent for quite a while, it seems, to appear in print) that in 4-deckers and beyond, the gain from employing more indices is marginal."
Use Wong & Griffin for strategy advice, & they also concur. Makes sense also. The more extreme counts are unlikely to happen & when they do any advantage from strategy variation will be marginal.
"But if you is able to memorize and deploy more than, say, the Illustrious 18, in a shoe, then go right ahead and do it!"
I only memorise -1 to +8, & is enough on the positive side except maybe 1 or 2 plays a month. (1 deck is cut from use). Doubling is only permitted on 10 & 11, so that's not many decisions to remember.
"If you can divide by half-decks, quarter-decks or even number of cards remaining, then do that too. More power to you."
I divide by half decks as I have a neat trick, but intend to divide by full decks at other games. Am lazy only play the one game :)
Thanks for your clarification of common true count reference, & additionals.