"play-all" approach
The "play-all" approach" is not the way to go.
Either is "wonging"
Both have severe drawbacks.
The best way is to "Wong-Out" as substantially negative counts that are not near the end of the shoe.
When to wong-out depends on the depth of penetration and the rules in effect.
as a general rule, if using Hi-Lo in a game with a House Edge of -.41 and dealing 75% of the cards, spread 12-1 (or 16-1 if you can afford it) and "Wong-Out" at True Count = -2 if there is more than a deck to play through heads up, or 1.5 decks to play through with 1 or 2 others at the table. or 2 decks at a full table.
