House edge when using BJ Basic strategy at a Spanish 21 table?

I like to take my Dad out to play Blackjack with a boost from some match plays, but unfortunately our local card-room recently removed all of their Blackjack tables and the only option we have is to play Spanish 21.

Now my Dad, having played Blackjack for more than 50 years, knows Blackjack basic strategy very well. He would not be able, however, to learn a new basic strategy for Spanish 21.

My question for the wizard is this:

If a player sat down at a Spanish 21 table (Hit on soft 17, redoubling allowed) and played Blackjack basic strategy, just how badly would this increase the house edge?

I don't think you said what rules he plays "Blackjack basic strategy" for. But ,it will roughly cost him about 0.5%^^^, if he normally plays basic strategy against the rules below:

6-deck, Stand on S17, BJ pays 3/2, no surrender, split once, no hitting of split Aces.

^^^:This figure doesn't include the cost of NOT playing the Spanish 21 bonuses correctly, eg playing for a 5-card 21 correctly etc.

Also, if you want to give him a simple boost, you can tell him always hit a hard "unpaired" 12 vs anything, and hard 13 vs anything***, for Spanish 21.


***: it is slightly better to stand on a hard 13 vs a dealer six, but this is just to try and make any possible Spanish 21 strategy variations as "easy as possible to learn" (if you think he can handle it?)

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Edit (about 535 pm, Pac Time):

If he is just playing it for the Match Play bonuses only, then there is probably not much incentive to learn another strategy, but if he also likes to play recreationally, then I would try to find out what plays/variations should be "easy to remember and / or have a significant effect on the House edge".

Thanks a lot for the input!

No, no match bonuses or anything. He was never one to play recreationally.

I wonder if playing for the bonus hands (6-7-8, 5 card, etc.) is negligible, or significant?

Quote: MountainBike

(snip)
I wonder if playing for the bonus hands (6-7-8, 5 card, etc.) is negligible, or significant?

I wouldn't know exactly, but I would guess it is closer to negligible, mainly because you would probably only "miss-play" on less than half of the hands that you are meant to hit (in other words hands that you would normally hit anyway, no matter the number of cards in your hand).

Also, here is a good link for Spanish 21 >>> https://wizardofodds.com/games/spanish-21/ <<<.
One thing it shows is that the overall maximum value for the Super Bonus is up to a 0.036% (with 8-decks).

" 11. Suited 7-7-7 when the dealer has a seven face up pays $1000 for bets of $5-$24 and $5000 "Super Bonus" for bets of $25 or over. In addition, all other players receive a $50 "envy bonus." This bonus does not pay after doubling or splitting."


"Super Bonus
The probability of hitting the Super Bonus is 1 in 668,382, with six decks, and 1 in 549,188 with eight decks. The reduction in the house edge depends on the bet amount, and to a lesser extent, the number of players. With no other players, and bets of exactly $5 or $25, the Super Bonus lowers the house edge by 0.030% in a six-deck game, and 0.036% in an eight-deck game. At a bet of exactly $5, the Envy Bonus lowers the house edge by an additional 0.0015% in a six-deck game, and 0.0018% in an eight-deck game, per additional player.

For bet amounts other than those indicated above, the benefit of the Super Bonus will go down as the bet amount goes up. "

Note: You may have already looked at this, since it is a "sister-site" to Wizard of Vegas.