I am not sure that Aces are the best side
count for Hi-Lo as the ace is already included in the count, thus making betting strategy the forte of Hi-Lo...and betting strategy is the more powerful element to winning blackjack...an ace side count with improve you playing strategy I will agree, but so will other cards you side count...just which is best is not clear to me and hopefully your question will spark some discussion from the experts on this site--i am merely a recreational player.
anyway, if you search this forum's archives for ace side counts you will come up with a post by Alienated that does a great job of talking about side counts...indeed, he even gives the link to a simple spreadsheet that will give you an alebragic generated set of strategy tables for any count system, plus any strategy tables for any system of side counts...but the spreadsheet is set up for single deck H17...I used the spreadsheet to come up with side counts for me. I am working on adding a seven side count to my Hi-Lo for use in single deck, thus the template works well for me.
In my experimenting with counting systems I found I can side count with Hi-Lo easier than using a level two count (such as Zen or RPC) without side counts. Sevens can also be factored into betting counts and insurance as well (I am sure that can be said of Aces also).
Why I picked sevens was I read a few posts in the archive, plus I looked at table of gains available in Theroy of Blackjack.
It seems that knowing how many sevens are left would work well with 12's, 13's & 14's vs dealer low up cards, while knowing the aces helps most when you double on with a 10 or 11.
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