Most online casinos/software differs in streaks run by the player & dealer, etc. I do believe there are times that you can ignore those basic blackjack rules when it comes to hitting in the occasions you listed above. What I will never understand is why most players always assume that the dealers face down card is another a face/high card. You can simply look at your own hands dealt, and pretend your 2nd card is face down. Is it usually a face card.....?......no, it's not. I do believe it takes somone with a good memory of past hands played though. For example, if I play 3 hands and the dealer's face down card was a high card each time, the next hand I may hold on 12-16. I have been very successful in the many years I've played online in winning hands by making the dealer bust. Think about it, how does the dealer win the majority of it's hands......by making you bust. As I said , it just depends on the software also, because I have been playing at one book's casino where the dealer beats me with a 6 showing 8 out of 10 hands and rarely every busts on that 6!! Im telling you, I am not exaggerating. I have been meaning to come on here and create a thread about it but never did, but thought I'd throw it out there.......