Statistically playing 20 hands is pointless, it's why I suggested playing a shoe. Of course players win sometimes or break the odds.

As I said before the maths are more complex, but if you follow basic strategy which HAS BEEN calculated a long time ago to be the optimal strategy (certainly better than sticking on 12+) the house edge at Evolution & Playtech casinos is 0.486%.

With your simple method the casino house edge will be larger, fact!