Blackjack / Probability / Strategy

BlackjackDeviations

Deviations are count-based exceptions to basic strategy. They are valuable only after basic strategy is already automatic.

Deviations

Indexes

What an index means

An index is the true count where the expected value of one play overtakes another. For example, insurance becomes attractive around TC +3 in Hi-Lo.

High-value deviations

Common high-impact deviations include insurance, 16 vs 10, 15 vs 10, 12 vs 3, 12 vs 2, and 10 vs A. These do not replace the full game plan, but they sharpen it.

Practice method

Drill one index at a time, then mix them into a playable table so the count, dealer card, and hand total must be processed together.

Frequently Asked Questions

FAQ

What are blackjack deviations?

They are count-based exceptions to basic strategy used when the true count reaches a known index.

What is the most important deviation?

Insurance at about TC +3 is one of the highest-value and most recognizable index plays.

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